My son, who is now 6 years old, is a typical boy. He's into trucks and balls and swords and wrestling. And yet, when he is around his baby sister, his tender side emerges, quite by surprise.
He loves to hold his little sister. He *tries* to carry her around. He likes to give her toys to play with.
He likes to put bowls on her head and laugh at her. :-)
They are both such a breath of fresh air for our family!