Thinking back almost 20 years.....
My youngest son Tyler, started shooting at about 3 years old.
He had an old Pearson solid glass bow. An old tube quiver that I rigged a strap on for a back quiver, and some wood youth arrows that I picked up. Everything was fine, and he was cute as a new pup!!
Only one problem... When he hit the 3D targets with the "bullet points" on the youth arrows, They would fall out.
AND HE WOULD TOTALLY LOOSE HIS SHi+!!!!!
With growing kids, my suggestion would be...
Get a simple 5/16" taper tool, and some good field points.(heavier the better, IMHO) Measure their draw, and cut the arrows a couple inches longer, then taper and glue on the field points. This will do 2 things. Make it easier to aim, using the arrow point, and make sure the arrow sticks in the target!!
Nothing is more frustrating to a kid, is knowing they hit the target and not being able to see WHERE they hit the target!!
I'm totally with you, on ordering bows!!! Everyone wants to spoil kids, LMAO!!!
I'm thinking about ordering a pink maple Little Squirt for my grandaughter and she's only 6 months old!!
However, a cheap glass bow will work just fine. The more they grow, the farther they pull it back, the more the draw weight increases... AND you can't overdraw and break it!!!
(something "stupid big kids" do when they try and shoot a bow that's too small for them)
This is just one old fart's opinion.... Enjoy them while they're young!!! They grow so fast...