Baby number 3 is 9 weeks old. And I cannot remember what age my other two found their own initial pattern of having three naps a day....morning, afternoon and cat nap before bed. She's still usually sleeping in short blocks and waking (or being woken!) after a short time and needing to get back to sleep again quickly as she's still tired. I can't predict her sleep at all.
I know she's still very young, and I'm not one for needing to get into a routine straight away, ive always let my babies find their own pattern....but it would be useful to know at what age your bub developed their own routine. Because I feel like I spend most of my day getting her to sleep!