Front Message: My Sister She’s as much like me as she is different. She’s smart in ways I’m not, and funny in ways I love. Inside Message: She’s stronger than she realizes. (I should know, I’ve seen her in action.) She's a great mother, a great friend, and one of my favorite people in the world. And I hope she knows it. Happy Mother's Day to awesome, amazing you This American Greetings Mother's Day Card for sister features shimmering foil embellishments. Card measures 5.375 in. x 8.25 in. Peach envelope included included. Standard postage required. This American Greetings Mother's Day Card is suitable for a special sister in your life.