It won't work. It rarily works for adults - and I'd guess it'd never work for a child. Mainly because the child would become frustrated and give up and then you'd have a neglected bird. Call you area Vets and ask for referrals to good breeders in the area. If it were me, I'd get the lovebird for a child.
Lovebirds are sturdier than parrotlets just because of their size.
Both birds are very, very active and can amuse their humans for hours. The bird will actually LIKE to be with people. You DO NOT get a bird thinking - we'll tame it after we get it home. It won't work. It rarily works for adults - and I'd guess it'd never work for a child.