When we first brought our little lady home from the hospital, our son was not having any of it.
He screeched every time he saw her. The whining went on for days and days, and I was convinced that this was just the way it was going to be.
Fast forward a couple of weeks, and he has really warmed up to her. If she cries, he runs over to see if she's okay, and he LOVES holding her in his lap. Sometimes he thinks her head is a drum, but most of the time he's super gentle with her. Maybe it has something to do with the fact that we started dressing her in his old clothes because NOTHING fits her, she's so tiny.
Or maybe, just maybe, he loves having a sister.