If you have a sister-in-law, then you will know the joy of being gifted with a sister a little bit later in life. For many people, a sister-in-law means a special lifelong friend that can be turned to for advice in difficult times, and belly-aching laughs in good ones. You also celebrate many of life’s milestones with your beloved sister-in-law.
When her birthday comes around, it’s important to let her know just how happy you are that she’s part of your family. Although she may not have shared your childhood, she will be around for a long time to come.
Feel free to adapt them in any way that you see fit so that your sister-in-law’s birthday message is one that will mean the world to her.
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• How to Say Happy Birthday to a Sister-in-Law
• Heartfelt Birthday Wishes For Your Sister-In-Law
• Funny Happy Birthday Wishes For Your Sister-In-Law
• Inspirational Sister-in-Law Quotes
• Sister-in-Law Poems
How to Say Happy Birthday to a Sister-in-Law
Personalized birthday wishes are always a lot more special than generic ones are, and your sister-in-law is bound to feel wonderful after reading hers. Below are three simple tips on how to personalize her birthday card:
• Most of us have nicknames for the people close to us. If you have one for your sister-in-law, use it in the card. By addressing the card to her nickname, she will immediately be reminded of the special bond that the two of you share.
• What makes your sister-in-law special? What makes her shine out from other people? Perhaps she is a great mother, perhaps she makes your sibling happier than you could ever have imagined, or perhaps she is excellent at giving advice. Either way, try to include something in the card about what makes her so special. Make sure that whatever you write to your sister-in-law comes straight from the heart. This could just be a personality trait, or perhaps even a memory that you treasure most. Including it in her birthday card will make for a heart-warming moment.
• If your sister-in-law has a special nickname for you, be sure to sign the card with that nickname. This will pull the card together quite nicely and reinforce the idea of the bond that the two of you share – what could be more special than that?
When composing your birthday message to your sister-in-law, don’t rush into it and write something that you don’t mean.
Sit down, relax, reflect and take your time with it. The more effort you put into the card, the more she will love it. It’s the thought that counts, after all.
Heartfelt Birthday Wishes For Your Sister-In-Law
• I am so unbelievably happy that you are a member of our family! May the coming year bring you every wonderful thing you have ever wished for. Happy birthday to you, my special sister-in-law! Sending you all my love always.
• So many people refer to you as my "sister-in-law" or my "brother’s wife" when they speak to me, but I like to refer to you by your other title: my friend. I hope your birthday is as fun and fabulous as you are.
• To my beloved sister-in-law; you’ve always gone out of your way to include me in so many aspects of your life. I want you to know that I appreciate everything that you do for our family so much. You are warm, caring and have a generous nature. My wish for you is that your birthday is joyous, momentous and prosperous. Happy birthday!
• My darling sister-in-law, you may be our parents’ newest beloved daughter, and my brother’s treasured wife, but you are also my best friend. Thank you for bringing so much joy and happiness into all our lives. May this coming year be meaningful and bright. Happy birthday!
• Sister-in-Law, thank you for showing me that I can always rely on you. No matter what the issue is, you are a constant source of help and support. Thank you for being such an understanding and generous person, and I pray that your birthday is as warm, bright, and wondrous as you are! Happiest of birthdays to you!
• Happy birthday to my amazing sister-in-law. You may not have been born my sister, but you're my sister all the same.
• To my incredible sister-in-law, I hope this year’s celebration reaches new heights of happiness. I hope it is filled with plenty of laughter, love and all the people you care about. Happy birthday!
• Happy birthday to my sister-in-law! You make every day so much brighter with your smile. I hope you are treated to all of life’s sweetest surprises, not just today, but always.
• To my sister-in-law and in life: happy birthday! You have been a treasured gift ever since you joined our family. I wish you plenty of new, cherished memories on your special day. Wishing you plenty of joy and love in the coming year.
Funny Happy Birthday Wishes For Your Sister-In-Law
Of course, everyone loves to receive a joke or two along with their birthday wishes. Take a look at some of our ideas for funny birthday messages for your sister-in-law:
• You drink too much, you cuss too much and you have questionable morals… you're everything I ever wanted in a sister-in-law. Happy Birthday!
• I smile because you're my sister-in-law. I laugh because there's nothing you can do about it! Happy birthday.
• Happy birthday sister-in-law! Another year of surviving my brother…
• I know our family may be loud and crazy, but at least we are crazy about you! Happy birthday sister-in-law!
• To my dear sister-in-law: I was trying to think of the perfect gift to give you for your birthday… but then I realized that you already have the best gift: me as your brother-in-law. I couldn’t possibly top that, so I went for this bottle of your favourite red wine instead! Enjoy it – I hope it brings you as much joy as you bring to our family.
Inspirational Sister-in-Law Quotes
If you want to highlight how much you admire your sister in law, these quotes sum this feeling up beautifully:
• "She is free in her wildness, she is a wanderess, a drop of free water. She knows nothing of borders and cares nothing for rules or customs. ‘Time' for her isn’t something to fight against. Her life flows clean, with passion, like fresh water."― Roman Payne. Happiest of birthdays to you, my sweet sister-in-law! May you continue to thrive being the strong, inspirational woman that you are. I love you!
• "Always aim high, work hard, and care deeply about what you believe in. And, when you stumble, keep faith. And, when you’re knocked down, get right back up and never listen to anyone who says you can’t or shouldn’t go on."—Hillary Rodham Clinton. You are the embodiment of this quote, my dearest sister-in-law. May you continue to inspire us all in the coming year. Happy birthday to you!
• "I’m a woman
Phenomenally.
Phenomenal woman,
That’s me."
—Maya Angelou. Happy birthday to one of the most Phenomenal Women I know. You are the best sister-in-law I could ever have wished for.
• "Fill your life with women that empower you, that help you believe in your magic and aid them to believe in their own exceptional power and their incredible magic too. Women that believe in each other can survive anything. Women who believe in each other create armies that will win kingdoms and wars." – Nikita Gill. Thank you for always believing in me, and for always empowering me. Happiest of birthdays to you, my sister-in-law.
• “If you’re comfortable with yourself and know yourself, you’re going to shine and radiate, and other people are going to be drawn to you.” – Dolly Parton. I see this in you every day. Keep shining and drawing people to you. Happy birthday, my inspirational sister-in-law. I am so thankful that you have joined our family.
• "Each person is born with very individual qualities and potential. We as a society owe it to women to create a truly supportive environment in which they too can grow and move forward." – Princess Diana. Thank you for creating a supportive environment for all of us. We can never thank you enough. Happy birthday, sister-in-law!
• “I am learning every day to allow the space between where I am and where I want to be to inspire me and not terrify me. I can even ask for help! Not feeling that I have to know everything…that’s where the growth comes in, in the not knowing.” – Tracee Ellis Ross. You help me grow with every laugh, with every tale and with every chat we share. Happy birthday to you, my darling sister-in-law.
Sister-in-Law Poems
• We weren't sisters by birth, but we knew from the start… Fate brought us together to be sisters by heart.
• As a sister-in-law, you're great. As a friend, you are the best. To have you in our family, makes us all so truly blessed.
• To a very special sister-in-law, a happy birthday's due. With a wish that the year that lies ahead is wonderful for you.
• God didn't make us sisters by birth. Instead, He gave us a friendship with more worth.
• You're a really special sister-in-law, and every now and then, it's good to have a chance like this to tell you so again.
• They can call you sister-in-law, or my brother's wife. It doesn't really matter – you're a special person in my life.
• I'm so lucky to have a special sister-in-law like you. May all your hopes and birthday wishes come true!
She may be your sister by marriage, but your birthday wishes can make her feel like family. Use these ideas as inspiration and pen a message that means the world.
37 Ways to Say “Happy Birthday, Unbiological Sister”
Having a sister is like having a built-in companion, but if you don't have any biological sisters, an “unbiological” sister can be just as special to you.
An unbiological sister is even closer than a best friend. She's someone you can rely on no matter what you're facing, who will support you, give advice, and listen to your secrets.
Close friendships between women not only provide emotional support, guidance, and companionship but can also improve your health! A study of breast cancer patients found better outcomes in women with larger groups of friends, even if those friends lived far away.
On your soul sister's birthday, it's lovely to take the opportunity to celebrate her and remind her how important she is to you.
Below, we have more than 30 “happy birthday, unbiological sister” messages, plus tips to help you create your own personalized options!
• Thank you for being my one true friend and sister, and for allowing us to do things together instead of competing. I love you! Happy birthday!
• Here's to bigger, better, and brighter years ahead. May your every wish come true this year, and may you only experience happiness and love. Happy birthday, soul-sister!
• BFF means Best Friends Forever, but do you know what SBFD means? It's “Sister but Friend in Disguise.” Happy birthday to my SBFD!
• Warm birthday wishes to a special lady who I'm lucky to consider a sister. You are truly remarkable, and apart from being your soul-sibling, I'm blessed to be your friend too. Happy birthday, girl!
• Cheers to another year around the sun. Happy birthday, sis!
• Happy birthday, soul sister! I'm really proud to be your best friend. I look up to you in everything, and I know you will continue to inspire me. Enjoy your day!
• Friends come and go, but family is forever. We might not be family by blood, but I'm honored to call you my sister! Happy birthday!
• I'm so blessed to have an unbiological sister like you. You are the greatest and deserve all the happiness in the world on your special day. Happy birthday!
• I don't know what I'd do without you in my life. Happy birthday, soul sister!
• Happy birthday to you today, my sweet friend! You're like the sister I never had and you mean more to me than you'll ever know. I'm confident that we'll be friends for life and sisters for eternity. Enjoy your special day — you deserve it!
• Happy birthday to my sister at the soul and a friend close to my heart! I hope your special day this year is everything you want it to be!
• We may not be sisters by birth, but we're sisters at heart and siblings by choice. I couldn't be luckier than to have you in my life, and I wish you the very best in the coming year! Happy birthday!
• On this special day, let me wish you good luck, lots of happiness, and love. In a word, I wish you an amazing life. Happy birthday!
• Happy birthday to that one friend of mine who will always be more like a sister to me! Love you lots, girl!
• Through thick or thin, I can always count on you. That's why I hope you enjoy your special day to the fullest! Happy birthday, [nickname]!
• My dear soul sister and kindred spirit, I'm sending my best wishes your way on your very special day today. We share a bond unlike any other, and I will always be grateful for having someone as spectacular as you in my life. Happy birthday!
• Sister (noun): a person who knows you inside and out. That sounds like you! I'm so grateful to have you in my life. Happy birthday!
• We may not be sisters by birth, but somewhere deep within me, I feel I've known you forever. You're my true sister, FOREVER. Happy birthday!
• A sister may fight with you, taunt you, scowl at you, or trouble you. But at the end of the day, she'll always love you. Happy birthday, my soul sister!
• You are the sister I got to choose. I'm so thankful for your friendship. You deserve the very best, and I hope [age] is fantastic for you! Happy birthday!
• Happy birthday to one soul sister from another! You mean the world to me, and I hope your special day is nothing short of perfection!
• We weren't sisters by birth, but we knew from the start… fate brought us together to be sisters by heart. Sister, I love you so much and hope you have an incredible [age] year! Happy birthday!
• In my heart, you will always be a true sister to me first and foremost, and then a friend second. Our bond has grown so strong that, to me, you are like family. May you have a wonderful birthday today!
• If we can't be biological sisters, at least we can be unbiological sisters for life! Here's to another incredible year! Happy birthday!
• Some friends are exactly that, and some friends are more like family. You're the latter. You're more of a sister than a friend. Happy birthday!
• Sending beautiful birthday wishes to my best friend, who is like family to me. You may not be my sister by blood, but you truly are by heart!
• A special friend I truly adore, in my heart you've earned sister status and so much more! Happy birthday!
• Because of you, I laugh a little harder, cry a little less, and smile a lot more. I hope this year you laugh a little harder, cry a little less, and smile a lot more. Happy birthday, sis!
• What do you wish for a sister-like friend as incredible as you, who is already so amazing and who has accomplished so much? Eternal joy and happiness, I guess! I hope that you always find contentment in everything you do and that the good always far outweighs the bad in life. You deserve every happiness! Have a marvelous birthday!
• It's hard to give up on my dreams when my unbiological sister is my cheerleader. Thanks for all you do, girl! Happy birthday!
• Sending lots of love and wishing you a sweet birthday today, my closest friend and true sister at heart!
• You're my closest friend and a true soul sister indeed! You're the driving force behind the amazing things that I do in life. Happy birthday!
• I've always longed to have someone I can call my sister. That's why I'm so grateful for having you around. Happy birthday!
• To the only one who can read my thoughts and moods without glasses, happy birthday!
• Happy birthday to my soul sister! Even though we're not related by blood, you have loved me more than my own family. Thank you so much. Cheers on your birthday!
• Happy birthday to the best gossip buddy on the planet, my one and only unbiological sister!
• My dear sister from another mister, you are a one-in-a-million find and a priceless diamond. Happy birthday!
How to Craft the Perfect Happy Birthday Message for Your Unbiological Sister
Your unbiological sister is undoubtedly one of the most important people in your life.
Since she means so much to you, a personalized message might be more fitting than a pre-written one for her birthday.
Keep the following tips in mind to help you write:
• Make it personal. Make references to memories, favorites that you share, or dreams she has for the upcoming year. The more personal your message is, the more meaningful it will be for her to read!
• Keep it light. A birthday is a celebratory occasion! You and your unbiological sister have probably been through a lot together, but it's best not to bring down the mood on her special day, so keep your message positive and sweet.
• Don't be afraid to get mushy! While it's good to keep the mood light, that doesn't mean you should entirely avoid emotion. If there's ever a time to share excessively sentimental thoughts and words, it's a special occasion like a birthday! Use your message to emphasize how much she means to you.
• “45 Unbiological Sister Quotes,” Mums Invited[↩][↩][↩][↩][↩][↩]
• “Birthday Wishes For Unbiological Sister: Best Wishes Sayings,” Congratulations Wishes[↩][↩][↩][↩][↩][↩][↩]
• “100 Touching Birthday Wishes for Sisters and Sisters-in-Law,” Good Housekeeping[↩][↩][↩]
• “Happy Birthday Soul Sister Wishes and Quotes,” Top Happy Birthday Wishes[↩][↩][↩][↩]
• “100+ Beautiful Birthday Wishes for Friend like Sister,” Happy Birthday Wisher[↩][↩][↩][↩][↩][↩][↩][↩][↩][↩][↩]
• “Poem About Friends That Feel Like Sisters, True Sisters,” Family Friend Poems[↩]
Lindsey Desmet