How do you say goodnight boo in french?

There isn't a direct translation for "goodnight boo" in French that carries the same level of intimacy and endearment. However, here are a few options depending on the level of intimacy and the specific meaning you want to convey:

Formal/Polite:

* Bonne nuit. (Good night.) - This is the most neutral and polite way to say goodnight.

* Passe une bonne nuit. (Have a good night.) - This is a slightly more affectionate way to say goodnight.

Informal/Affectionate:

* Bonne nuit, mon amour. (Good night, my love.) - This is a very romantic way to say goodnight.

* Dors bien, mon cœur. (Sleep well, my heart.) - This is a sweet and endearing way to say goodnight.

* Bisous, mon chéri(e). (Kisses, my darling.) - This is a playful and affectionate way to say goodnight.

* Bonne nuit, mon petit(e) lapin(e). (Good night, my little bunny.) - This is a very cute and endearing way to say goodnight, using a pet name.

Using "Boo":

* Bonne nuit, mon petit(e) boo. (Good night, my little boo.) - This is a direct translation that uses the English word "boo" but adds a French touch with the "petit(e)" (little).

Ultimately, the best way to say "goodnight boo" in French depends on your relationship with the person you're talking to and the level of intimacy you want to convey.