Hi @Krista, thanks for writing to us, and I apologize for my delay in getting back to you! I am not a dentist so I’d ask your dentist next time you go, or ask your pediatrician, but it would be my guess that sucking on the zipper would be his way of soothing like some babies may suck on their thumb or a paci. Of course over time this can cause issues for their teeth, but I will not pretend to know the science and details behind all of it or when it starts. Here is a link to read more about infants and pacifiers that may give you some more information if you are concerned: https://www.babysleepsite.com/sleep-training/pacifier-newborn-infant-sleep/ I hope this helps!

@Nicole – Thank you for reading and for sharing with us! Sleep sacks in themselves don’t usually hinder development when used properly. You generally want your baby’s limbs to be able to move around freely for a considerable part of the day to ensure development so we generally advise they not be in the sleep sack or swaddled up all day long. As long as your baby or toddler is in the “right” size, it is not mandatory to wean from the sleep sack at all really. If you’re concerned about her development, please reach out to her healthcare provider soon for reassurance or ideas. If you need assistance in weaning her from the sleep sack, please consider connecting with one of our sleep consultants. You can read more about them here:https://www.babysleepsite.com/about Hang in there, Nicole and best wishes to you!