My step dd is 14. I’m younger than her dad so we are more like friends. Recently she had a sleepover at our house and it transpires her and her friends are messaging a much older actor (50s) I won’t name him as not relevant and he’s fine nothing wrong. They were quite open and showed me messages and replies (them flirty and he was appropriate in his replies). They have also made TikTok’s calling him a dilf etc. is this ok to just let them get on with it or do I need to tell her dad? She trusts me so I feel it could damage our relationship and no danger of anything happening as he is a celebrity and in another country!