She may just be a later bloomer, which is no cause for concern. The point made about babies sleeping on their backs contributing to the problem in crawling, is very valid. The muscles babies need to use in order to crawl, develop when they are on their tummies. That is what “tummy time” is so crucial. The irony is that we out babies on their back to prevent (supposedly) SIDS chalilah, when 30 years ago the prevailing wisdom was that putting them on their BACKS led to SIDS. And now with the sleeping on the back all the time, babies are developing “flat-head” syndrome, where some of them need to wear special helmets to re-contour their misshapen skulls.
NY Mom’s advice was extremely sound.
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