Why did he rub a tomato on his bottom?

I am soooo excited. I was planning to start full-on potty training on Monday, so I had the pottys upstairs. Jacob woke up from his nap, and went to the bathroom on the potty! I was downstairs, totally didn't even know what he was doing until Jonathan told me. Needless to say I was pretty excited! So, later this afternoon I was watering my garden and the boys followed me outside. I have to share this because for some reason it cracked me up! Jacob picks all of my underripe tomatoes (I wasn't too happy about that). Comes in and gets a fork, then sits, naked at his picnic table and eats them. I was cracking up! So then, for some reason Jacob rubs the tomatoe on his bottom (I know, tmi) and his whole bottome brreaks out in this red, rash. So apparently he is allergic to tomatoes. I'm not sure why he rubbed the tomatoe on his bum. I couldn't even get mad about the tomatoes, although I am sad he took ALL of them off the plant. So, potty trianing begins. Wish me luck!