There is never a shortage of love that a grandparent has for their grandchild. It would seem to be easy, then, to express those feelings at important events like the birthday of a granddaughter.

Despite how cold and formal the “sister-in-law” title sounds, those sisters are still family. And be that the case, they deserve every bit of love and acknowledgment that our blood relatives get—hey, ...

A good message is an essential part of celebrating someone’s birthday. When it’s your sister-in-law’s birthday, though, you want to create a great one. A thoughtful, well-written message can make a ...