Hi! Congrats on the baby twins!!
They are very little still so keep in mind that sleep will be a bit off and on especially for the first few weeks. Nothing will really be consistent for a bit so many hugs and hang in there! You're doing great!
And yes, your situation seems very common! It happened with my LOs where we had 1 good nap during the day and the rest were short. It could be in part to A times but also just developmental as well. The way I tried to see it was:
0-3 mths they work on their night sleep.
3-6 mths they work on their day sleep.
There will be many changes but as long as the "routine" or eat play sleep stays consistent-- you will be at ease in the future!
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babies thrive off routine!
Remember at this age too, OT is inevitable! What I did was do my best to get as much sleep as possible at that age and tweak ATs or always keep them in mind
Is the morning nap something you want longer?
Hope this helps!