to tell it to him/her
Are you going to tell him?
— Wake Up Dead Man : Une histoire à couteaux tirés (2025)
Parce que tu vas aller le lui dire tout de suite.
Because you’re going to go tell him/her right away.
— La Main de Dieu (2021)
I forgot to tell him/her.
Je l'aime, mais je ne sais pas comment le lui dire.
I love him, but I don’t know how to tell him.
Je lui ai promis de ne pas le lui dire.
I promised him I wouldn't tell him.