two brothers

two little boys go into the grocery store. one 9 years old, the other one is 4. the 9 year old grabs a box of tampons from the shelf and carries it to the register for check out,    the cashier ask's, "oh, these must be for your mom, huh?' the 9 year old shakes his head and peplies, nope, not for my mom. '" cashier; ''well , they must be for your sister then?  9 year old; nope, not for my sister  eighter.''  cashier, curious now; ''if they are mot for your mon and sister, who are they for? the  9 year old says,  ''they're for my 4 year old brother.''  surprised, the cashier  ashs, ''your little brother right there??'' the 9 year oldexplians; ''well, yeah!they say on tv--if you wear one of these, ---you can swimor ride a bike, and my little brother can't do either!''