Our little fish stopped sleeping from 8pm to 5am at about 3.5months. He started waking for an extra feed between 2am and 3am. It wasn't until he was nearly 5months that he's stopped waking up. This last two weeks, he's slept from 6:30pm until somewhere between 5am and 7am with his last feed being at 6pm. Fingers crossed I haven't cursed us to broken nights sleep now!