L.B.
At first glance I thought you were saying your kid liked boys butts. Whoa. Okay, so the kids are at an age where they are typically just mimicking what they see/hear and think is what they are supposed to do. At age ten my son had a girl send him an email signed "your sexy girlfriend". Needless to say I wasn't thrilled. I think you were right in telling her to leave that kind of thing for when she's grown up. I still think they can have pizza with grandma, this is an age where they are learning how to relate to the opposite sex and going to pizza with grandma is a perfect, harmless way to do just that. Just relax but definitely keep your eyes and ears open. Sounds like you are able to comfortably talk with your daughter and that's wonderful!