Hi new moms! Wandered over from 2nd tri to ask about crib bedding. Currently trying to decide on the set that I want to help determine what color our son's nursery will be. What is considered "safe" is always changing. I've heard nothing but the mattress should be in the crib. What are you using? Did you purchase a set (i.e., 4 piece, 5 piece, etc.) and do you have any buyer's remorse? Any insight would be great. Thanks so much.