A Jay Bird moment.....

Have you ever hear the phrase "naked as a jay bird"? If you haven't, now you have. Why do I bring that up? Well, it goes like this....Laurel has invited her friends over to play the other day. They are like the 3 musketeers. You don't much see one with out the other two. Very cute little girls, but can be your typical girls when together...squealing, giggling, the works. Anyhow, the time came when Kately was picked up by her mom and then we were waiting for Bailey's dad to come. Laurel and Bailey were having a good time playing upstairs so no worries that he was a little late. When he did come, I yelled up for Bailey with no answer. So I trudged up the stairs to get her. I could hear them giggling in Laurel's closet so I opened the door to find them both......completely nude. My first thought was "AHHHHHHHHH!!! what the heck??!!" and my second thought was "AHHHHH!!! what are you doing??!!" but instead I was calm and told them both sternly to get their clothes on quickley and come downstairs cause it was time for Bailey to leave. I went downstairs and continued idle chatter with Bailey's dad and waited. Once she left, I calmly pulled Laurel into a private room and told her that she was NEVER to do that again. We don't play nude and if someone even suggests it we say NO!! I never yelled or sounded upset. I know that it is a "normal" thing for kids to do....be curious about their bodies and others. I had to have a moment of relief that it wasn't a boy in the closet cause then I may have lost my cool. My question is this: would you say something to the mother of the other girl or let it go completely since I already addressed it with my own child?