100+ Birthday Wishes for Your Cousin Sister To Make Her Special Day Sweeter

HBW Editorial Team
HBW Editorial Team
Created and reviewed by our editors

birthday wishes for cousin sister

Our beautiful birthday quotes and touching wishes are the perfect way to tell your cousin sister how special she is on her birthday. Just pick the one you like best, copy and paste it, and send it to her on WhatsApp, Instagram, or other platforms!

  • Happy birthday, cousin sister, who is beyond a sister to me. You're my best friend for the rest of my life. May you have the most wonderful birthday like the wonderful person you are. 
  • Happy Birthday to my sister from another mister. I wish you have the best birthday and year because you deserve no less. I am always thankful to you for having my back in sadness and in joy like a true sister. 
  • Although we are cousins by label, deep down in my heart you are my real sister and I only wish your special day is as special as the bond we share. May all your dreams come true and may you have that beautiful smile on your face forever. 
  • Happy birthday and many happy returns to my cousin, who is undoubtedly my spiritual guide and sister at heart. Just know that no matter how much I tease you and no matter how much I make your life a living hell, you mean the world to me and I always have your back, just like you got mine. I know even though you say you hate me, you love me the most. You are my favorite person on the planet and this is the only time you get to hear it. 
  • Wishing my favorite cousin the most wonderful birthday ever! May you continue to soar higher and shine brighter with each passing year!
  • Happy birthday to the brightest person in my life who is also my cousin by birth but my sister by bond. May your birthday bring the brightest smile on your face, and may your birthday be the little sprinkle of happiness on the platter of joy in your life.
  • Wishing my beautiful cousin a very happy birthday, with whom I share a bond so close like sisters share among themselves. And It is only natural that you have a birthday as sweet as you, and a cake sweeter than that. 
  • To my beloved cousin sister, whose presence brightens even my darkest days and whose unwavering support is a constant source of strength, I send you the warmest birthday wishes. May our bond continue to grow stronger, and may our shared adventures be filled with joy, laughter, and love. Here's to creating unforgettable memories together!
  • Cousin, my wishes for you this year are simple: have the most wonderful day!
  • Happy, heartfelt birthday to my dearest cousin, who is not just family, but also my forever best friend. From the infinite number of memories shared to the laughter we've echoed through the years, your presence in my life is a treasure beyond measure. You bring warmth, understanding, and a special bond that feels like home to your family.
  • On this special day, I want to express my gratitude for all the moments we've shared and the ones yet to come. May your birthday be as beautiful and radiant as your soul, filled with love, joy, and blessings. Here's to celebrating you, my beloved cousin, and the incredible person you are. Cheers to another year of adventures, laughter, and love! 
  • Happy Birthday to my dear cousin sister! As you celebrate this special day, may it signify the start of another wonderful year and an exciting new chapter in your journey. May all your dreams and desires be fulfilled, and always remember that you are truly very special. Wishing you the very best!
  • May your birthday cake be the mirror of the sweetness you bring into our lives every day, and may your heart be filled with warmth and happiness as you blow out those candles. Happy Birthday sis and may life showers you with all the blessings that the universe has to offer. 
  • In this family, your smile shines like that ray of sunshine which brightens the environment after a cloudy day. Happy Birthday sister, may your laughter always fill the air and may your love always fill our hearts. 
  • Many happy returns of the day, cousin, and wishing you a very happy birthday. To me, you are not just a cousin but also a sister, a confidante, and my best friend.
  • To the sweetest soul I know, and to my partner-in-crime, here's wishing you the happiest birthday. May this year bring you an abundance of health, happiness, and success. Cheers to many more years of sharing smiles, creating memories, and being the amazing person you are! Happy Birthday, sis!
  • Happy birthday, dear cousin! You're more like a sister to me, and I'm grateful for the laughter and the memories we've shared. May our bond continue to grow stronger with each passing year, and may we always be the joyful tornadoes that brighten each other's worlds. Best wishes on your special day! 
  • Sending best wishes to my utterly cool cousin sister and wishing that this birthday is the best birthday you had till now. Happy Birthday and congratulations on growing another year older, but I would always be smarter. 
  • My special and beautiful cousin, may your birthday this year be just as dear as you are to me. Happy birthday to my best friend and sister at heart, who also happens to be my partner-in-crime. 
  • Happy birthday to your sister. May your special day bring you as much happiness as you've brought me over the years, and even more. All the best for your upcoming adventures!
  • Happy birthday, my adorable little cousin sister! May your special day be a beautiful one full of love, joy, and happiness!
  • Happy birthday to someone who is more like my own sister and less of a cousin, and also my best female friend. Sending lots of love and hugs for you on your special day.
  • Happy birthday to someone with a beautiful soul and a heart of gold: my cousin sister. Your presence in my life makes it so much sweeter.
  • Happy birthday, girl! A sweet cousin like you is a beautiful blessing! You are someone who is so very special and inspirational to me: my dear elder cousin!
  • Happy birthday, girl! Best wishes from your favorite cousin!
  • Happiest Birthday. Wish you have a day as beautiful as you and as special as our bond, much more like sisters than cousins, and I wouldn't change that for the world.
  • Wishing you a truly wonderful birthday, cousin! You deserve it more than anyone!
  • Cousin, you always have and always will be the absolute best person to have by my side. 
  • Happy birthday, girl! You might be my cousin, but you're so much more like a sister to me!
  • Happy birthday to the best cousin sister ever! I hope your special day is as special as you are to me!
  • You'll always be like a sister to me, cousin. You're just as dear and can be just as annoying! Happy birthday!
  • Birthday gifts are nice, but gifts like me comes once in a while. No gift will ever be as great as having a funny cousin like me! Cherish while it lasts, and please don't forget that it is your treat this time. Happy Birthday!
  • Happy birthday to my fabulous cousin who still isn't showing her age… or acting it, either! Here is wishing for you to grow up a bit more and remain as wonderful as you are. 
  • Happy birthday to my fabulous sidekick! Here's to sharing many more adventures and ice-creams together. 
  • Sometimes crazy, sometimes silly but always pretty, you're my cousin sister, and you will always be my favorite human! Happy birthday, sis!
  • Congrats, cousin! Here's to many more years of laughter and creating wonderful memories together! Happy Birthday!

happy birthday wishes

Happy birthday to my best friend
and sister at heart, who just so
happens to also be my cousin! 

Have a great day, girl!
My cousin, spirit guide and sister at heart
Cousin, you'll always be more like a sister to me
Happy birthday, my dear!

We might have been born into our family
as cousins, but the truth is that really we
are much more like sisters!

I hope that your special day brings you as
much happiness as you have brought to
me over the many years!

You deserve nothing but the best life has
to offer, my dear!

Big kisses!
We have a close bond, cousin
My heart says we are sisters
I’m sending the very best birthday wishes your way today, my adorable little cousin sister! May your special day be a beautiful one full of love, joy, and happiness!
A cousin sister who is utterly cool
Sometimes crazy but always amazing
A family member like you isn’t just a beautiful addition, but a true blessing.

I feel so lucky to have you as my cousin, and even luckier that I’m able to call you my best friend and sis. Your presence in my life is heart-touching, as you truly mean the world to me.

Happy birthday to you today, my dear.
Having a cousin like you growing up meant that I had the best childhood possible.

To me, I’ll always see you not only as my cousin but also as a best friend and sister.

Happy birthday to you, and thank you for all the happy memories, my dear.
You're just like a sister to me, cousin
A cousin who still isn't showing her age
For someone who is a cousin, a dear
friend, and also a sister to me, I thought I
had better get you not one gift, but three!

May you have the absolute best and
happiest birthday possible today!
A cheeky cousin and a true sister
Happy birthday to my amazing cousin
Happy birthday to my partner in crime!
Or should I say, my fabulous sidekick!

You always have and always will be the
absolute best person to have by my side.

I hope you have the most wonderful
birthday ever today, my dear cousin!
My darling cousin, congratulations on yet another incredible year!

I’m a strong believer that blood is thicker than water, and particularly in our case, it couldn’t be any more accurate! Our bond is so close, more likened to that of sisters, and I wouldn’t change that for the world.

Have a truly wonderful birthday, my dear! You deserve it more than anyone!
Happy birthday, my dear!

I’m wishing you much greatness and joy on your special day this year, as a sweet cousin like you truly is the most beautiful blessing!

I’m so grateful even to have you as a family member and the only thing that could be better is if you were my sister, just like you already are in my heart. 
For a cousin and a sister all rolled into one
I’m wishing you a birthday that’s full of fun!

Happy birthday, my dear! 

Here’s to the many years of laughter and 
creating wonderful memories together 
that are still waiting to be written!
Happy birthday, my dear cousin!

We have so many funny and precious
childhood memories that I realized it
would be impossible for me to pick
just one as my favorite!
It’s no wonder people mistake us for
siblings rather than cousins because I too
sometimes forget that you are my cousin
as you’re so much more like a sister to me!

Happy birthday, my dear! I hope your
special day is as special as you are to me!
My dearest relation, who isn’t only an incredible cousin but also an amazing friend and sister to me.

I wish you happiness today on your birthday, and forever more!
Officially you’re my cousin, but my heart
says you’re my sister. Luckily for you, I
always listen to my heart!

Happy birthday to you, my dear. I
hope you have a truly wonderful time
celebrating your special day today!
You are so very special to me, my dear cousin, and it’s no secret that I have always been very protective of you as I have always seen you as more of a little sister rather than a cousin.

When we were kids I’d only want the best for you, and I knew then that you too would always have my back.

It’s such a joy to see that now you’re getting older, you are developing into this incredible and beautiful person!

Happy birthday, my dear, and I hope that today brings you all the happiness in the world, which you so very deserve!
HBW Editorial Team
HBW Editorial Team
Happy Birthday Wisher relies on a team of writers, editors, poets, and enthusiasts to produce, organize, and review all the content.

You might also like