I don't think that's illegal, but I'm no expert. Morally, however, you're in kind of a grey area.
Talking to younger girl. I'm 21. She is 17. BOTH of her parents have stated that we can be friends.Our relationship is NOT physical.I have not solicited her in ANY sexual manor.My question is, am I doing anything illegal? State: Louisiana
No, not legally: https://www.age-of-consent.info/states/louisiana
I am not into automatically avoiding all potential hazards, but I am into risk analysis. So, look at the big picture; follow the Golden Rule; and know the potential hazards in evaluating this relationship.