Okay, today was my first day back to work/school. DD is 2 months old. She has never taken to a bottle. We were trying Nuk nipples, she didn't care for those. So, we are now trying the playtex nurser system with the wider nipples, shaped more like a mother's breast (I suppose.) Anyway, the daycare worker told me she is used to sucking harder than she needs to with this bottle and the nipple is collapsing. Any suggestions? I just spent a bit of money switching to this system. Is Avent better? Do the Avent nipples work with the Playtex bottles?