Sometimes religious rites should not be allowed, when it harms a creature that cannot consent this should true.
Why not alter things so that the child can 'choose' when they are older after indoctrination/religious education, at the very least they get to consent. Let the child do it when they are a young man. The Masai do that, if you make it through that you really are a man.
http://www.circlist.com/rites/maasai.html
Again, they are indoctrinated, etc, but at least you can choose to run off into the bush and live like a hermit with your foreskin intact should you so choose.