Campervanning with baby

Just before finding out we were expecting we bought a camper conversion which wasn't ready until December so we haven't actually been able to do anything more than a day trip so far. I'm not due for another couple of weeks but we are keen to get out and about overnight as soon as we can. Our family have a field with no facilities about an hour away we can use to get used to how things work with the baby and its close enough to pack up and come home if we arent feeling. We are also looking at drive away awnings so that we have a little more space etc. My question is, for those who are experienced with camping with their baby, what did they sleep in? In relation to clothing and their bed. There isn't enough space for a travel cot so I was initially thinking for short 1 or 2 nights they could sleep in the carry cot of their pram but when they've out grown that I'm struggling to find something suitable. I'm also worried about what would be best for them to wear as I don't want them to get cold during the night or overheat.