- You don't seem like Al's daughter.
- Actually, I'm not. He's my son by a previous marriage.

7 seconds sound clip from the The Best Years of Our Lives (1946) movie soundboard.

You can hear this line at 00:41:44.611 in the Blu-ray version of the movie.

Quote context

[...]

- Hey, Butch. You know Among My Souvenirs, huh?

- Shall we dance?

- Well, that's a charming idea.

- Do you remember this tune?

- Nice to see the young folks enjoying themselves, isn't it?

- So you're Al's daughter.

- Yes. I've been that as long as I can remember.

- You don't seem like Al's daughter.

- Actually, I'm not. He's my son by a previous marriage.

- What did you say your name was?

- Peggy.

- Peggy, my name's Fred. How do you do?

- How do you do?

- Oh, no, you don't. Oh, no.

- You know, you're a bewitching little creature. In a way, you remind me of my wife.

- But you never told me you're married.

- Oh, yeah. I've got a little woman and two kiddies back there in the States.

- But let's not think of them now.

- Oh, you're so right. This night belongs only to us.

[...]