Hi C.,
Babies are creatures of habit. If this is the habit he is in, he will stay there until you break it. At 4 months (unless a premie) babies can go through the night without the need to eat. So this isnt a need he has. He needs the bottle to soothe himself back to sleep. I would break that asap. Different moms have different opinions on whether or not to let their babies cry it out. I am believer in letting them cry and its worked well for me. They have to learn to self soothe. Its a tool they need as they grow. The first few nights he may cry for hours its hard on you. But after a few nights the time will get shorter and shorter... and in the future if he wakes up in the middle of the night, he will know how to get back to sleep on his own. However, if you are against letting him cry, I would at least replace the bottle with something else. Maybe some sort of blanket or stuffed animal. Try and replace it with something that can stay in his crib and he can learn to use that to soothe. The problem is if you repalce the bottle with cuddle time, or rocking, then you are just teaching him to rely on you now to go back to sleep and he is still not learning to sleep through the night. I know its hard because no mother likes to her their baby cry. We associate that with pain and our instincts want to make it better. But this is really a skill that you need to teach him for the future. Good Luck