Most 9-week-old babies need about 14–17 hours of sleep each day, split between short daytime naps and a longer nighttime stretch.

Most 11-week-old babies sleep around 14–17 hours in 24 hours, split between longer night stretches and several daytime naps.

An 8-week-old baby usually sleeps 14–17 hours in 24 hours, split into short daytime naps and a longer stretch at night.

Children’s sleep needs by age range from about 12–16 hours in infancy to 8–10 hours in the teen years, with younger kids sleeping the longest.

Most 1-month-old babies sleep around 14–17 hours in 24 hours, split into short stretches by day and night.

Most teens average about 7–7.5 hours of sleep a night, which falls short of the 8–10 hours experts recommend for healthy growth and learning.

Most teenagers need 8 to 10 hours of sleep each night to stay healthy, learn well, and manage mood.

Teenage guys usually need 8–10 hours of sleep each night, with many doing best near 9 hours for steady energy, learning, and healthy growth.

Most teens need 8–10 hours of sleep a night, with many doing best near nine hours of regular, good-quality rest.

Babies need around 11 to 17 hours of sleep per day, with total hours gently dropping as age, feeding habits, and development change.