I wasn’t sure how to wish you a belated happy birthday, but I thought it would probably be best to start off by apologising for missing the actual day!
Sorry for the late wishes, I hope you can forgive me! Happy belated birthday!
Happy birthday, sis! On your special day, I want you to know that no matter how old we get, the fact will always remain that you are my younger sister and I’ll always be there to look out for you.
You’re my little sis and I care about you and love you a lot! I hope you have a fabulous birthday today!