A thread in IMHO right now (the one about male-on-male action in the 50s) reminded me of a movie moment. I saw it on TV as a pre-pubescent teen (so I didn’t know exactly what she meant) and this puts the TV broadcast in the early 80s at the latest. There are a group of teens in a tent at night. There is only one girl. She offers to leave the tent for a while if the guys needed/wanted to “round the rosie” or “ring the rosie”. That’s all I remember, just the setting and the phrase.
Have at it.