My son will be turning 5 months old on the 16th. He has always been a very good baby. Doesn't get too fussy, loves interacting with people, smiles and giggles a lot, tracks perfectly, always gets great checkups. Though he hates tummy time, he is tolerating it, and we try to do it 5-10 minutes a few times a day. He can support all of his weight on his legs perfectly as well.
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 I have noticed lately though that he seems to be behind in using his arms. He likes to hold them in front of him, pull them apart, and suck on them, and will grip onto an object that you place in his palm like a finger or rattle. But beyond that, he doesn't reach for anything. I have tried all sorts of toys and he just stares at them, with his arms to his side. If I lift up his hands they usually just drop right back down. Sometimes he will provide resistance but normally they are limp. He hands are also usally pretty cold. Not alarming cold, just chilly, though I suspect that might be because they are in his mouth a bit.
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In tummy time, he will prop himself on his forearms, but not do much else. I can't entice him to roll over as we isn't interested in any toys, or object at all. He would really just rather look at people and faces, and smiles and giggles and makes raspberrys.Â
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I put him in a Bumbo and he sort of sits up, and will sometimes flail his arms and sway at the toys, but thats about it.
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I am not sure if I am being too paranoid, or if he is just slightly delayed.
