Hi M.,
I have a 7 1/2 month old, and he has been sleeping through the night since he was 3 months old. Occasionally, he will wake up in the middle of the night if he's not feeling well or has an exceptional amount of pee in his diaper. :) I think when my son was around 6 months old, he went through a period of 3 weeks of waking up around 1:30am, but he had a cold that lingered on. I never feed him when he wakes up in the middle of the night because I don't want to get into that habit (and I heard that after 4 months, they don't need to eat in the middle of the night, anyway). I just change his diaper if it feels really wet, or snuggle for a little while to calm him down (only he's not feeling well, of course). And sometimes my guy will wake up crying and go right back to sleep. So maybe wait a few minutes before you go check on him... but I personally don't let him cry if he persists, because he doesn't cry unless something is wrong.
Other things to consider, is he eating solid foods, and if so, what time does he eat "dinner?" Whether you're nursing or not might make a difference, as well. If he's teething, maybe some tylenol will help.
So hang in there, maybe he just has a cold, or is teething. I wouldn't worry if it's only been a couple of days.
Good luck,
E.
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