He is currently (exactly) 8 months old. His father is about 15-16hh, and his mother is 14.1hh. He was separated from his mother at 2 months old, and has only been eating hay since (mid-quality grass/alfalfa). He is kept in his large pen, which is about 60x30ft with a 30x10 run in shelter. Most of his exercise is in those confines. His owner occasionally lunges him hard for about an hour at a time, but there could be two weeks in between when that happens.
For his age, exercise, and nutrition, does he appear to be developing correctly? I know the pictures aren't the best, and I am not able to remove his blanket. Underneath his blanket, he appears to be ideal weight though. His hindquarters seem thicker than his shoulders (compared to every other horse I've dealt with, where the two areas are about even).
Also, what do you think about his front knees? His father has beautiful conformation, but his mother's knees are dramatically knock-kneed. Every foal I know has awkward legs, so it's hard for me to tell if he inherited his mother's knees or not.
The first picture is of his mother when she was pregnant:
These pictures are of the colt at two days old:
This picture and video are both of him in the past week, at 8 months old: