In 30 - 45 minutes after the baby is asleep, he goes into light sleep phase. (bebezclub.com)
When you regenerate the watch can provide detailed sleep tracking like duration, deep sleep and light sleep phases as well as awake times. (us.amazfit.com)
This means that every single hour of the night your baby goes through a «light sleep» period where she will either be able to settle herself back to sleep fairly effortlessly or she may need a little help getting through the light sleep phase back into deep sleep. (thebreastfeedingblog.com)