So...we’ve got a 6 month old son who has from birth been a relatively good sleeper. By about 3 months old was mainly sleeping through the night. In the last 4 weeks I have not had one full night sleep. He goes down around 8pm and Wakes anytime between 1-2am but will not go back down into his cot. I have tried for like 2 hours some nights but we end up having to go downstairs so that my partner can sleep as they are at work early. He is eating solids and drinking the milk that he should during the day. And no matter how he naps during the day it has no effect on his sleep at night. I now absolutely dread going to bed knowing I’m going to be up all night. He will only sleep whilst I hold him however I do not want to co sleep with him as I worry too much to be able to sleep then. Any help at all would be greatly appreciated. We are both struggling and extremely sleep deprived