I have a rocking crib that I borrowed from a friend for my newborn DS. When she lent it to me I thought about getting a new mattress for it, but for various reasons decided not to ( I know I should have! ). The mattress in it is a foam one and was used for her DD for less than 6 months, but there is a bit of a dent in it where the baby has been. I'm struggling to get DS to sleep at night ( have posted about this elsewhere ), but he sleeps quite well during the day in the carrycot part of his pram. Putting aside the fact I should have followed the guidelines and bought a new mattress, will a new, thicker, maybe a sprung one help him to sleep better? He is a bit windy/colicky, are there any particular types that would help with that?