Hi OP,
I was in a very similar situation with my first son regarding him needing to be fed to sleep for both naps and overnight. It was utter hell and I was exhausted. I co-slept with him as it was the only thing that enabled me to get any sleep but when he was 10 months old i just couldn’t take it anymore. I was just so, so tired. I can’t bear to even think about it.
I used a sleep consultant and she said the most essential thing to do first is to get baby into to his own room.
I know you said he will have to share with his sibling, (I’m not sure if you’ve said how old the sibling is) but whilst addressing your baby’s sleep could your other child sleep somewhere else? A make-shift bed in your room maybe so that there’s less chance he’s disturbed at night whilst doing some sleep training?
When I used the Sleep Consultant she spoke to me about all the different types of sleep training she did and the main focus was, “How quickly do you want this fixed?”
I opted for controlled crying and she completely changed my son’s daytime routine (his naps and meal times) as well as his bedtime routines and within a week I had a completely different baby.
I won’t lie, the first few nights were really tough but I had reached breaking point. I was in such a dark place and my marriage was on the rocks because we were fighting all the time because we were just exhausted. I spent most of my time crying and I was hating being a parent. It was just awful.
She was really, really fantastic and she saved me in lots of ways…. She certainly saved my sanity and my marriage.
I went from a baby who was up at least 4 times a night (for up to an hour at a time) who needed to be breastfed back to sleep every time, and never napped in the day, to a baby who then slept from 7pm to 6am (self settling) and had two naps a day in his cot (each nap being 1hr 20 minutes) without needing to be breastfed to sleep for those either. My baby was getting almost 7 more hours sleep per 24 hours after the training compared to how much sleep he was getting before and so you can imagine how much better that was for him too, as well as for me.
If you would like more information please private message me.