It's neither. There have been studies that showed that they don't need more sleep, but are naturally on a later circadian rhythm. Young kids are on a early cycl

It's neither. There have been studies that showed that they don't need more sleep, but are naturally on a later circadian rhythm. Young kids are on a early cycle. Once they become teens the cycle shifts to later hours and then in the 20s starts moving forward again. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4648699/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4648699/