I think it really depends on how it's done.
Giving a child a sense of religion which ends up crippling them with guilt, stifles their freedom, produces self loathing, promotes hate, discrimination, fear of others, fear in general, a limited knowledge of life, science, art, history etc. and/or a dislike of anything away from their religion is a horrible thing which damages a child and makes them a damaged individual whether they know it or not.
Giving a child a religion which opens them up to the spiritual world and endless possibilities, gives them a dedication to charity and kindess/compassion, shows them love for all humanity despite the frailties and weaknesses, gives them strength when they are vulnerable, gives them courage against injustice, teaches them their minds and character are valuable, that you should seek knowledge, suck out the marrow of life and to good things will lead to a very well rounded, happy individual.
People are different, children are different, they can be affected in different ways, religions can all be either of the above examples. The way people teach religion is different. there are many variables. But many people will simply teach religion the way it was taught to them, full of fear and restrictions which play no part in modern society. And others will break free of those teachings and take a different path.
I will teach my children what I believe but when they're teenagers and inevitably ask "how do we know" I will tell them that nobody does and that I believe what I do because of x, y and z. I just deeply hope that they gain from religion all the things I have and carry those gains with them through life.