Thanks for the reply
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We've almost given up on EASY at this point, reason being that with the short naps, we were feeding him every 2-2.5 hours, which resulted in symptoms of lactose overload. We spoke to a lactation consultant and she recommended giving up and going back to a more on-demand feeding i.e. skip some feeds post waking and only feed him if he wakes up hungry. We've done that and the symptoms are better.
That said, a typical day might be
7am wake and feed for 30-40 mins (he's a slow feeder, although started to get quicker last week or so. He sucks for comfort, as I mentioned)
7.30-7.40 play/cuddles in bed with mum, dad leaves for work
8.15-8.30 try to put down for first nap, down by 8.30-8.45 ish, mum has shower/breakfast etc.
9.15-9.30 wake up, feed
10.00 play time on his play mat, probably some tummy time once food has gone down
10.30-11 aim for down second nap
11.15.-11.30 wake up, feed
12.00 in rocker while mum makes lunch
1.00-1.30 mum maybe takes him out to shops/visit friends, he sleeps in pram/car.
3.00 wake up, feed
3.30 play time
4.30-4.45 nap - probably on mum
5.15-5.30 dad gets home, wake up, feed, then play time with dad, parents make dinner
6.30 in rocker while parents eat
7.00 bathtime, lullaby
7.15 final feed before down around 7.45-8.30 depending on how much he fights it
It's a bit erratic as it depends on what commitments mum has during the day, but he'll usually be out at some point (even if just for a walk and some fresh air), and that's more likely to be a longer sleep (although lately less so).
We usually try to put him down sometime between 1.15-1.30 depending on when he shows tired signs, but if he's being difficult to put down it can end up being 2 hours awake. He's always had longer than average awake times - even when only 6 weeks old he wouldn't go down until 1.30 (you could set your watch by it), no matter how early we started trying. An earlier put down time just seems to mean longer settling time.
Today for the first nap I tried a longer than normal wind-down, starting at around 1.10 before he was looking tired, but gradually removing the stimulation rather than putting him straight in the cot. It still took a while but he went down peacefully at 1.35 rather than crying. Still only slept 45 minutes though. I tried the same thing again for the second nap after about 1.10 waketime (he was looking tired) and it didn't work at all, he just stayed awake (happily) and simply wouldn't fall asleep until 2.30. Naturally he's been overtired all day.
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I'm pretty sure he doesn't have reflux, he doesn't have any of the symptoms and he's quite happy on his back in other situations - on a play mat or change table for example. It's only when on his back in a cot, wrapped up and with the lights dimmed that he starts crying - he seems to know that it means nap time. We've tried not wrapping him, but he just flails his arms about everywhere and doesn't settle at all.