We experimented again on Friday night with putting E and A to bed without swaddling them. Cue two hours of screaming! A eventually settled, but E just got more and more worked up until she actually made herself sick. As soon as we swaddled her she calmed right down and we were able to put her to bed five minutes later. We weren't keen on the prospect of repeating the experience after every night feed so we swaddled A as well after the 11pm feed and the rest of the night went better.
I think we'll be sticking with the swaddling for a while longer. A manages to get his arms out of his, but it's pretty clear that they both need to be swaddled to get themselves off to sleep, and I don't see any harm in it for now.
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