Ahead, find thoughtful, funny, and inspirational birthday wishes for any sister in your life. Happy birthday to my built-in best friend. You are undoubtedly one of the best people I know ...

Birthday wishes for sister-in-law. I’m so glad you’re joining our family. Happy birthday! Happy birthday to my sister-to-be! Happy birthday to my new sister! Thank you for marrying [sibling name], we ...

From funny birthday captions to sweet ones, these birthday wishes for your older or younger sister are perfect ... Thanks for being my IRL babydoll (and for letting me put lipstick all over ...

Oh, siblings—the ones who’ve had your back since day one. Give your brother or sister a special birthday wish to express your love for them. 88. Happy birthday to a fabulous [brother/sister].

Sweet birthday messages for your sister-in-law. We may not have been raised together, but it feels like I’ve always known you my whole life. Happy birthday, and thanks for being the best.