As an ex-catholic, all I can say is: if your kids grow up with enough common sense and pragmatism, they might resent the early indoctrination. Their brains have not matured enough to develop common sense until their teens, and everything the adults say will be taken as absolute truth. The humane thing would be raising them atheist, explain about agnosticism and religion, and accept their choice. All the rituals can be done at any age.

Just like religious parents can have atheists kids, atheist parents can have agnostic or religious children. Indoctrinating them from childhood is taking their freedom of choice and choosing for them.