Has he got his two year molars yet? I found that when my girls started to get their molars, sleep was EXTREMELY disrupted until they came through. Other than that, I've got no advice except to struggle through. The great thing is, you know that he can sleep through, so he will eventually go back to that. He's just going through a tough sleep period. Our DD2 has started sleeping through again after a tough period that lasted five months (I don't mean to scare you but it can last that long). She was getting her two year molars. I'm talking waking up at least five times a night. Twice a night was a good one. There was nothing I could do except give her cuddles and help her through it. Now that they are through, she's sleeping through again. I knew she could do it, I just had to wait. Sorry if this post isn't much help. I just think that if they have been able to sleep through before, they will do it again, we just have to be patient unfortunately! sending you some sleepy vibes xx

PS there are other techniques you can try like controlled crying but that wasn't for us. I just couldn't do it. One because I hated hearing her cry, two because her cry is so loud it rattles my brain out of my head and three because it would wake DD1 up. I don't judge people who use it though. It does work for some people.

PPS we bought an amber teething necklace, which helped a little. Not a magic cure but it did help x