On my post below I should've put my post-nursery church bag philosophy.
My kids each have their own bags. Spencer's is pretty small, and Conner just has a scripture bag (with a small pad of paper and a pencil in it).
P will have a moderately large bag probably til' she's about 2 and then it will get a bit smaller, and smaller... She will take her own things into church (possibly with a little help for the first few months) but it will be her bag, it can not be opened until after the sacrament, but she can look at the friend or a "church" book before that. I am on the fence about treats. She often doesn't eat too great of a breakfast on Sunday mornings. I am guessing I will bring a very small bag of either cereal or fruit snacks and a sippy cup.
This bag then heads out to the car after Sacrament meeting so I don't have to lug it around. :)
My good friend Lara has really taught me that after the little one goes to nursery, less is more. I've tried it, and I agree.