Defiance stated: source post
Erm, no. Crawling comes before sitting up in like every single baby i've ever seen ever.
Are we to believe you've watched every single baby you ever seen, develop ?
They first flip themselves over onto their front, often while reaching for smth far on the other side, and then figure they can use their limbs to get up from that position.
They roll over onto their stomachs, and this helps the back and neck muscles develop. The infant will arc with their hands spread out. At this stage they can only do it for a short while, and the arms wouldn't be strong enough either.
Going from lying flat on the back to sitting is a harder thing to do.
I don't recall saying the first time I got up was a tummy crunching sit up, but rather a grueling struggle.
You were probably trying to turn over, but you've changed and embellished this memory over time the more you've thought about it.
In doubt you'd argue you know one's reality better than they, that is the mark of faultiness.
Plenty of practice sitting upright (plus tummy time, too) will help your little one to develop the upper body strength he'll need to eventually start to crawl and stand up — which will eventually lead to baby's first steps.
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Crawling is your baby's next big achievement after sitting up. Crawling is usually, though not always, a key step on the journey to walking.
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Some people are known to stand before they crawl. Same could be said between sitting and crawling, but there is a generalization of the typical.
It's not that I'm an expert in any of this, but I took it upon myself to look it up.
I know what I experienced and it's my memory.
Sitting up was hard. It's right next to trying to get up without any working muscles. At 4 or 5 months, trying to get up requires such strain, getting on all 4's with the head up, then crawling when the muscles aren't ready, doesn't happen till they're ready.
Any baby that's strong enough to crawl, can already sit, as crawling is a bigger task then getting up to sit on our asses. It was like that back then, and even as we grow up, sitting up remains more efficient between the two tasks.