Wish your sister or sister-in-law a happy birthday with our list of 100 birthday messages for sisters. From sentimental to funny, choose one to write in a card.

Happy birthday to the most incredible sister figure! Enjoy today, chosen sister! Happy birthday! Your energy, kind soul, and big heart are just a few of the reasons you’re like a sister to me. Happy ...

Happy birthday, sister. I can’t believe you wanted to marry into this wacky family. I guess you must be just as wacky as the rest of us! Best wishes on your birthday, sister-in-law.

Regardless of your beliefs, wishing your loved one a happy heavenly birthday can provide a sense of comfort while giving you ...

Whether you’re looking for birthday wishes for little sister, your big sis, sister-in-law, or even your chosen sister, finding the right words to honor the day she was born will bring a smile to ...