Hi guys,
This sounds very much like what I'm going through with my second son right now.
He will be 11 wks in two days. For a while he would have done one good nap of about two hrs and the rest cat naps but now they are all short.
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My first boy was a catnapper. I had always put it down to the fact he wanted to be rocked to sleep! So at four months I started pu/pd to stop the reliance on rocking.
Around five months, his naps started to get better. I remember the very day it all started getting better.
I had put him down for his nap, could hear him stirring at the 45 min mark so headed up to get him just as normal (I never tried to resettle) and couldn't believe it when I went in to find he had gone back over to sleep!
I thought it was all because of the sleep training that he was finally transitioning to another cycle, but maybe he was just ready to do better naps regardless. I'm hoping my second son will be ready to do better naps soon! Its very hard to find time to spend with my first boy when the second is up and down from naps like a yoyo!