I spent a lot of time worrying about length of sleeps with my first and it's true, you definitely a little more mellow with subsequent children!

Do you wear your baby? I found I had all these problems with my first and clock watched constantly, even attended sleep school. With my second, I wore him a lot more and he slept well like that. Sometimes you just can't get them to go back to sleep and that can last for a few weeks or more....it's can be really difficult fighting it all the time, so I would just let my boy get up, maybe go for a walk in the pram an hour of so after, a drive in the car......keep it chilled out, maybe feed him back to sleep. I find there is normally another sleep either later in the day or night time and they catch up...some days not but others 2-3 perfect 3 hour sleeps.

As for the freakish perfect sleep, ah yeah, I know about that....I think my boy has finally decided to sleep all the way through (5 hours!) but I'm a little suspect in case he changes again!