Yeah, and one of the things that a coworker had told me when my eldest started playing youth sports (tee ball, soccer, etc around ages 5-7) was that the only difference between the kids that seemed like they were "good" and the kids that didn't have a clue wasn't talent. It wasn't natural athleticism. It wasn't a predictor of future performance.
All it meant is that those kids had older brothers, so they were more exposed to sports before they started at the bottom rung than those who didn't have older brothers.
Give it a few years from then, and it evens out to where talent/athleticism starts to become the differentiator. Because what you did before you were 5 years old doesn't matter.
A little story to buttress this point:
My oldest (just turned 6) just finished his second year of Rec BB. These teams "play" on Saturdays in March. The schedule consists of half an hour of practice then a roughly half hour game.
Given their limited skills the refs are extremely lenient so things like Travelling, Double Dribble, etc are basically not called. However, I really screwed up not getting him prepared for year one because it was my first experience with it so I (wrongly) thought that you just dropped your 4/5 year old off cold and they'd work out the rest.
The first year he played, I hadn't even worked on dribbling with him before we showed up. Mostly this was because it starts in March and I don't have an attached indoor basketball court and it is generally cold and snowy in Ohio in February. Anyway, I felt bad because my son was woefully unprepared compared to the other boys. The first thing they did in practice was dribble up and down the court and my son was the only one who basically looked at the coach like 'what is dribble?'.
Year #2 was MUCH better. My son is pretty tall for his age so he was good at rebounding and made a few baskets over the course of the season.
That is just one example of where having an older brother would help immensely. If his younger sisters or brother want to play, I will KNOW what I need to teach them in advance so they'll show up ready to go.
Another example from that experience that is kinda funny:
With almost all of these teams, they usually have one kid who can do it and the others basically are unnecessary to the team. Seriously, the other three on the court (this is 4-on-4) basically just get in the way of the one who more-or-less knows what he is doing.
Last year we had one kid on our team who was small for his age so he looked tiny on the court but he could dribble and shoot and he was BY FAR our best player. Most weeks he showed up with only one parent and no siblings so I didn't know why (in retrospect the other parent was probably busy with the older brothers). Anyway, the last week of the season he showed up with both parents and . . . three older brothers. That was an "Ah-ha" moment in which I immediately realized why he was so much better than the rest of the kids on the team. He had been playing basketball against his not one, not two, but three older brothers since he could walk so he was WAY better at it than the oldest kids like my son.
