Two little boys go into the grocery store. One is nine, one is four.
The nine-year-old grabs a box of tampons from the shelf and carries it to the register for check-out. The cashier asks "Oh, these must be for your mom, huh?" The nine-year-old replies, "Nope, not for my mom."
"Oh. Well, they must be for your sister then?" says the cashier without thinking.
"Nope, not for my sister either." says the boy.
The cashier had now become curious. "Oh. Not for your mom and not for your sister -- then who are they for?"
"They're for my four-year-old little brother." says the kid calmly.
The cashier is surprised: "Your little brother?? WHY?"
The nine-year-old explains: "Well, they say on TV if you wear one of these, you can do lots of stuff like swim, run real fast or ride a bike - and my little brother can't do any of those things."