My son has never been tested for peanut butter, just stayed away from it as he has allergies to egg, oats, and barley. Well my daughter was eating pb and toast, he got some on his hand, smeared on his face. He just turned 2. I noticed a few minutes later and wiped it from his face.
His face swelled up and was red with hives all over it. Took him to the doc and he's fine now, eyes still puffy though.
I'm just glad he didn't eat any of it!! Crikey! Really scary though. Least now I know for sure he DEFINITELY cannot have it!