Whenever! OK baby is now 9 weeks but still. Roughly every 3 hours but does randomly go 1.5 or even 3.5 hours. some days it will be exactly 3 hours all day, but then 3 days ago it was every 1.5/2 hours and I was on here asking what was happening. At night she was doing a 6 hour stretch between feeds (7/8 ish until1/2 ish) for about a week or 2 but for the last 2 nights hasn't gone more than 3.