My 6yo caught her dad and me "in the act"

Last night, my 6yo caught my husband and me for the first time, and I'm unsure whether to talk to her about not telling anyone or if I should just leave it alone.We leave the door cracked because of the baby, keep very quiet, and always check that the 6yo is asleep first. In 6 years, it's never been a problem.Well, we were, um, repositioning ourselves, my husband looked up, and there's our daughter standing there. She said we were being too loud (it was the neighbors; idk what they were doing, but they must've dropped something big in the parking lot), then just turned around and went back to bed. My husband and I couldn't help but giggle from embarrassment for a bit.As a family, we're very open and honest about everything. When I got pregnant with her brother, we told her the truth about how it happens, just leaving out the fun part. The problem here is that I don't want her talking about it at school and have the school think we just engage in sexual activity in front of our children. Any advice appreciated. via /r/Parenting https://ift.tt/2UjrUJi