We're having very similar issues here, so it could be an age thing. although DS is still having a short day sleep and I haven't been brave enough to cut the bottle out yet. He is taking well over an hour some nights to calm down enough and stay in bed. I don't have any tips, but at the moment, one of us is sitting by his door so he can see us and then lying him down every time he gets out of bed. It still took an hour tonight but I'm hoping this might work in the long run.
My tip is to be consistent with the routine and flexible with the times. DD2 was taking over an hour to get to sleep until I moved her bedtime to later and now she's out within 10 mins.
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