evidence: Sleeping through the night [...] As babies get older, feeding around the clock becomes less common. By six months of age, many sleep researchers say that healthy, normal-weight babies don't "need" to feed at night, at least in terms of nutrition. (Lactation experts often disagree, pointing out that, left to their own devices, babies still wake to feed after six months of age.) But waking and needing a caregiver for other reasons is still common. This is especially true throughout their first year of life, when babies are most vulnerable and their nervous systems the most immature. [...] If you liked this story, sign up for the weekly bbc.com features newsletter, called "The Essential List". A handpicked selection of stories from BBC Future, Culture, Worklife, Travel and Reel delivered to your inbox every Friday.