You just hit upon a key point - It's his rifle, let him decide!! Father may know best, but father isn't carrying, shooting, or cleaning it!!
Ruger youths are good guns, no doubt about it, Tikka is making a youth now, I prefer the Mossberg, which are less $$, and love the stock lengthening concept, I've had a few friends buy them and have shot a few (very impressed!!)
But, when my DIL gets her rifle, it'll be a Tikka Youth, probably a 7-08.