Baby Crib Mattress??

Claudia

My cousin is buying us our crib& changing table for our babyshower, Butttt she’s Only getting me the Crib and changing table NOT the mattresses for either one. I’m a FTM and I don’t know how to choose the mattress for both items. What do you guys recommend? I’m Looking for something Affordable and safe for my babygirl to sleep on if she’s comfortable laying on her belly