Funny Dirty Joke

a mother has realized that her three little boys have been sick lately she takes her children to the local doctor and the doctor runs some test and says the kids are low in iron in there blood so she decides to go to the local hardware store and buy some iron BBs and starts putting them in the kids food. A couple days later the youngest one come up to his mother and he tells her that he has been pissing BBs so the mom tells him not to worry bout it cause she has to iron BBs in their food so the iron levels in his blood and the youngest walks away ok with it then later that day the middle child comes up to his mother complaining about how he has been shitting BBs and the mother tells him the same thing as the little one but then after the middle one walks away the oldest come up to her and before he says anything the mom says let me guess u have been passing BBs to and the oldest responds with no i was out behind the shed jacking off and i shot the dog