My DS - a twin, with a sister - also began throwing things from an early age. That evolved into hitting things. By three or four he was so proficient at hitting things he one day hit a line drive with a whiffle ball to my mother's eye which caused her to have to take a trip to the Mass Eye and Ear Emergency Room for what they thought was a detached retina, and ever since that day, one pupil has been much bigger than the other, causing quite a stir when she has to see any new doctors!
And put it this way, he is still playing baseball in college. We also have pictures of him dressing up in his sister's bathing suits and tutus, etc, he and his sister had a lot of fun playing together. (And she can also whack a whiffleball pretty good!)
I did see something interesting one day. We have a transgender child in our neighborhood, male to female. DS was out in the yard playing whiffleball with his friends, and this child was out playing with the girls in the neighborhood. All the girls went over to a swing set and began playing on the swings, but this child didn't go with them. She stood next to the fence with her hands on it watching DS and his friends play, and didn't move for probably a half an hour. She has also knocked on our door before to see if DS will come out to play catch with her. I don't recall any other young girls in our neighborhood ever doing that before.
Speaking of DS - this thread made me think of this. He had to write a paper in his college sociology class on why it is BEST to raise a child gender fluid. I went to the same school and remember writing a similar paper by picking a side of our choosing (if I recall the subject was infanticide) and making a cohesive argument one way or another, for or against. FTR, my argument was "for", claiming that if late term abortion was ok, then infanticide should be, too. IIR I got an A on that paper. And no, I do not think infanticidem or LTA is ok, it was the argument that was important, and being able to see both sides of an issue. Idk if the latter is always being taught in colleges today.