I bet his weight will catch up all on it's own. Just like kids, they seem to have growth spurts where they seem taller or longer before the weight catches up.
He is still so young. My Tiki was also bony, skinny, and it took her 2-3 years to get to a healthier looking shape. She is also tall and long. Now at 5, she is the only one of my 4 who doesn't need to lose a little
