The 45-minute intruder

So Jack and I have been working on naps this past week. Jon has been out of town and it was a good opportunity to just stay home and focus on teaching Jack to take solid naps in his bed. We'd been working on this before, but after spending 10 days traveling, meeting new people and spending the majority of time in sleeping in someone's arms, we needed a refresher course.
Jack's been super about going to bed at night. He goes down without a peep and sends himself off to sleep with no trouble. But for some reason naps have been a little more difficult. Babies must be much smarter than we realize. I've always wondered how he knew the difference between a nap and his real bedtime. He must be very intuitive.
At this point, Jack takes about 4 two-hour naps a day, he usually starts out strong in the morning, but like most babies, finishes off the day a bit more fussier than he started. One thing I've noticed is that he wakes up about 45 minutes into each nap, but if I went to get him he was still clearly tired. Tracy Hogg (author of the Baby Whisperer) calls this the 45-minute intruder. How clever! Apparently, babies' transition from REM to deep sleep after about 45 minutes, during which time they are easily woken. Most times Jack's able to get himself back to sleep, other times I have to give him a little assistance, and still other times it's a hopeless cause and he just needs some snuggle time with mommy. But I'm learning to be patient and wait it out a little before rushing in to rescue him from The Intruder. Oh the monsters we moms must learn to battle!