So my for year old😵

My for year old daughter cought me an her dad having sex she usually sleeps the whole night and has never came to our room at night but last night she opened the door so quite we play music during it so we didn't hear her she set quite on the floor and got a free show when we finally noticed her I panic and took her to bed in hope to talk to her about today we'll all morning during breakfast all she could talk about was daddy putting his face in mama cookie that what we call a vagina in our house lol I'm so lost on how to go about this an enbresses I don't know how much she saw and how to even explain to her what she saw