Oh, Mrs. Sellner's probably mistaken.
6 seconds sound clip from the Mrs. Doubtfire movie soundboard.
You can hear this line at 01:12:48 in the Blu-ray version of the movie.
Quote context
[...]
- Miranda, what are you home early for, dear?
- With the court liaison Mrs. Sellner.
- She says that Daniel has some woman living with him pretending to be his sister!
- I told her he doesn't even have a sister.
- Oh, Mrs. Sellner's probably mistaken.
- Oh, she's a social worker, dear, really.
- And, besides, how could he replace you and so quickly, really?
- She's supposed to be older and very unattractive.
- Really?
- Mrs. Doubtfire? Did you and Mr. Doubtfire ever... You must've had your share of problems.
- Oh, of course, dear. What marriage doesn't?
[...]