UNEVEN---- BUTT CHECK

We were riding home last night and I was tell Keegan and Kaley that I had to take Alexander to the Dr for his 9 month check up. Kaley asked if he was getting shots, and I said no, they are just going to prick his finger. Kaley wanted to know why. I told her to check and see if he is anemic. Well as we know a car with 3 kids and the radio can cause hearing difficulties. She said to me " Mom he isn't uneven, he is just a little chubby" Anemic= uneven??? She thought I said "check to see if he is uneven" I guess is a loud car it might sound the same!! I just died laughing and then to make it worse Keegan asked what is that? I said they are gonna check his blood!! Keegs response "CHECK HIS BUTT??"
Check his blood= check his butt??? AGAIN Loud car!! My kids need hearing aids or I need to talk clearer