Often things say they are not suitable for allergies because they are made in the same place as something made with ie dairy, or nuts, or whatever; which means there would be a small risk of a trace. Someone on the last thread checked somethingnwith a baker in Sainsburys who said the actual specific bread was whatever-free but because of the risk of being made in the same place. Not sure if I am making sense.
If I was looking after a child I would of course want to know how things are done at home, but I meant that if another way works for them then they should do that (within reason). So wanted to reassure you that although O is tricky to put down in a cot for you he might not be for your mum or MIL, or might be for one but not the other etc. Te rtw will be stressful enough I think for you so as long as they know how you do things I wouldn't worry about going out of your way to make things easier for them as they will muddle through to find what suits them. Like we have to. When DD1 went to the CM she did all kinds of things she wouldn't do for me. They'e funny like that.