The unwritten code of teenagedom is that younger siblings are annoying. It probably stems from trying to distance themselves from the immaturity they believed they left just a few years before. You didn't have to actually be mean to them to be cool, you just had to roll your eyes at their simplicity. You could also demonstrate your superior sophistication by either humoring, or ignoring them. However, it was usually un-cool to engage with them.
He was the baby in His family, so He never had younger siblings. He did however become an uncle when He was 11 years old. He was a dichotomy for a tough 17 year old athlete. No one who knew Him on the football field, or the basketball court would ever imagine He had such a soft spot for kids.
He babysat, as well as attend His nieces' dance recitals. At my house He played with my younger brothers and sisters (I was the oldest in a very large family). My father was a very engaged parent, but he was not physical, he was quite reserved. He, however, was game. He would get down on the floor and rough house with my younger siblings. He threw them around. They climbed on Him. He chased them. He let them catch Him. He played ball with them. He played tea party with them. They climbed all over Him, and He never got tired of it. I think it worried my mother sometimes (there were more bumps, bruises, and band aides after He came along). I never had to worry about canceling a date because I had to babysit, we would just take them along.
I think you can tell a lot about the goodness of a person by how they treat children, whether they engage with them, find joy in their silliness, and by how well they accommodate their limitations.
...one more reason I love Him.