I think that what you need to do is start waking them up from their naps at the 1.5-2 hour mark - don't let it go a full 3 hours. See if that helps them be able to fall asleep more easily at night. What you are likely experiencing (IMO
) is that they still need a nap, but not as long of a nap as they used to - but they aren't regulating their own wake-up times well which is why you should do it for them with a self-imposed nap limit of 2 hours (maybe 2.5 hours - no longer than that definitely).