Mrs. Cartman calls Sheila (Kyle's mom) Carol as in "Carol, where are the port-a-potties?" Then a little later, Sheila calls Sharon (Stan's mom) Carol! as in "Can I borrow your cell phone, Carol?"
The "Carol" thing I think is supposed to be a joke. At the time, they hadn't established first names for any of the moms yet, so in this episode, they just had them all call each other Carol since it's a fairly generic female sitcom character's name.