I have been in a similar situation where I have had a child in my care for a succession of months prior to the allergy being identified. I did chose to keep the child on and became a peanut free home. It wasn't difficult as I don't have processed foods that may contain traces, and PB is not in my house. I had a much harder time with controlling the parents and what they served for breakfast. The amount of children who come with pb and jam smeared behind ears and in hair daily is crazy, even after numerous verbal and written requests regarding the peanut allergy. It's like these parents have a head like a sieve, or have never come across these kinds of allergies and are somehow oblivious to the reality surrounding potentially lethal allergies. I would never knowingly take a child with nut allergies on and the more time goes on, any allergy. Not just for liability but simply because it is a lot of work after a while. If you are peanut free then it's a much easier allergy to deal with than egg or dairy for example. I have a current little guy who has just developed an egg allergy so now I have had to change my pasta and it just seems like these days there is always something and its just getting old. Kiwi, dairy, egg and cream cheese(separate child from dairy) are all foods that my gang between them can't have, oh and a child who is allergic to dog saliva. ((sigh)) lol