Jill,
I don't know much about allergy testing or if your child will develop new
allergies as they get older, but I do know that peanuts (peanut butter) is not
a good idea.  I believe this is a very common food to be allergic to and it is
overused with the toddler set because it can be easily eaten in little finger
sandwiches (we are also led to believe that it's a pretty good food).  If I
had to do it over again with children of that age I would serve a little meat
(possibly leftover from supper or very small turkey burgers etc.), a soft
vegetable and fruit.

Don if you read this - question.  I was going to ask you this and I think it
applies here also.  What's the paleo take on seed spreads?  I believe I saw in
the health food store sesame seed (butter) spread .  I know I can't handle nut
butters but a seed butter? - might even be good for a toddler.  Thanks, Jane