"Nighttime sleep" refers to the period of restful slumber that happens during the night, typically when it's dark outside. It's the time when we go to bed and sleep for several hours before waking up in the morning. Full definition
It also features a built - in canopy and several attached toys to help provide your child with the perfect environment for nighttime sleep, daytime naps, and so much more! (abckidsinc.com)
Whatever you do, don't try to keep your child up longer during the day in hopes that it leads to better nighttime sleep. (babieslounge.com)