I know that we haven’t been on the best terms recently, but if I’m able to love a person so much, then I’m confident I can use this special day as an excuse to start loving his/her sister.

On your special day, I wish you a life full of joy, tranquility and prosperity.

I wish you a happy, successful and prosperous year ahead because you are such a special sister-in-law. I hope your birthday turns out to be a very memorable event.

Happy birthday to my phenomenal sister-in-law. May your birthday bring you as much happiness and joy as you bring into the lives of others. God bless you.

Today is your special day, my dear! May your dreams that are yet to materialize start materializing from this remarkable day.

To the most stunning sister-in-law on earth, I say thank you for being the wonderful person you are. I wish you a marvelous 30th birthday celebration.

You have been like a mother to my husband and a teacher to our children. It is times like these that make me think that our family would not have been the same without you.

You were always there when we needed your help and supported us in both the good and the bad I could not have wished for a better sister in law!

Having you as my sister in law made this family just a whole lot better! With your infinite wisdom and feminine grace, you have made not only my husband but also our children better people.

We may not always see eye to eye, but we must use the love we share for your brother/sister and make this special day a new beginning for our relationship!

Getting to know you at first was a rough deal, but I’m sure that in the process we will find common ground on the one thing we both love endlessly.

Double the children double the trouble! Today is an exceptional day for me as it is not only the birthday of the love of my life but also of the sister that came out right with him!

Getting along with your in-laws has always been a daunting task. Having you as a sister in law though felt like having a little sister!

Getting to have you as a sister in law always made family meetings much more exciting and filled with your youthful energy!

Always being the wise one in the house, you made sure to help the love of my life grow to the most fantastic person possible! I genuinely thank you and wish you the happiest of birthdays!