Posting this through tears of frustration! My nearly 5 month old was sleeping brilliantly from about 10 weeks. He would sleep from around 9 til 6 with only occasional waking which the dummy or white noise would put him back to sleep. But now he can't even make it til midnight without at least 2 wake ups and nothing will settle him apart from feeding. He is waking at least every 2 hours, sometimes more and it's really hitting me hard since he previously slept so well. This has been going on for about 3 weeks. Ive heard of the 4 month sleep regression and this is some major regressing! I'm wondering if anyone else's baby did this and went back to sleeping through or what might help? The dummy and white noise don't work anymore. He is mostly breastfed but does occasionally have bottles of formula. We have tried formula before bed but it made no difference.