Vernix caseosa, also called birthing custard, is a white, cheese-like substance found coating the skin of newborn babies. It is produced by dedicated cells and is thought to have some protective roles during fetal development and for a few hours after birth. Image by: https://www.instagram.com/p/CPsnC_Vn0o1/?utm_medium=copy_link
Does it plays any role in movement of baby in Aminiotic sac?
Yes it naturally acts as a lubricant helping the baby to slide out of the birth canal.