I've heard that they're supposed to just start sleeping through their 40 minute cycle at some stage (maybe 6 months???) because they can get themselves to sleep. I'm not sure how to speed up this process.
Try not to have too many expectations about what your bub 'should' be doing by a certain age - just ends up being incredibly frustrating for you (& bub!) when they don't do what they are 'supposed' to LOL :wink: I think Kynan was about 7-8m old, if not older, when he hit his catnapping peak LOL.