S.H.
My son is 16 months old and was almost exclusively nursed for a year unless there was a sitter, etc. We could only introduce cow's milk through a bottle at that time and he is still using a 1 or 2 because I refuse to buy more nipples - I hope he'll take it from a cup soon! Doesn't bother him but I have heard that it's easier to transition kids to a cup by cutting a hole in the nipple (didn't work for us) so maybe a larger nipple would help with that. Is your child frustrated with the bottle? You might want to try a sippy or move up with the nipples in that case.