I teach lots of kids in a few dif formats. An 8 year old child should not struggle. Many bows marked are marked for draw length beyond what a child can draw. As they grow the DW automatically goes up.
Now here the thing. Fellows excuse me as imo the advise is well intentioned but kids today are very often physically weak. I’m amazed at how much so very often. There may be some children among them that aren’t but asking anyone else doesn’t help.
You need to take the child personally. Make sure he attains full draw and doesn’t struggle. If you aren’t fully able to coach I’d advise getting help. No sense teaching bad habits. Check eye dominance. Show proper stance,bow arm, grip, release (no dead hands), follow through, etc.
If you need help w any of that pm me and I’ll help best I can on phone.
I use string bows to teach form and believe that’s the best way to do do.
Remember, what’s best for him, not the neighbor. Good luck