My mum stayed with us for two weeks over the summer and DS (8mo at the time) went from 5-6 wakings and rarely sleeping more than two hrs at a time to, by the end of her stay, 3-4 wakings including a gargantuan 4 hr sleep at the beginning of the night.
As soon as she left his sleep went to pot again. He hasn't slept for 4hrs since and is back to 5-6 wakings.
What's that all about? She played with him lots and did a lot of the caring - everything except nursing and overnight stuff. And breakfast as she was busy doing her hair in the mornings.
We didn't muck about with his routine or do any particularly exciting activities but it was obvious he loved having her here. So is that all there is to it? He slept better because she made him happy?
Would love to find out what it was so that I can replicate and have my lovely sleepy baby back!