Why does my baby move constantly while sleeping?

It is very common for infants to roll, crawl, or change positions frequently during sleep, especially when they are mastering new physical milestones. These movements are often a normal part of development as babies practice their new skills in their sleep. However, if your baby is rolling onto their tummy, always ensure they are placed on their back initially for safe sleep, and monitor them closely until they are strong enough to change positions comfortably on their own.