Amy Farrah Fowler: Who’s Tam?

Sheldon Cooper: He was my best friend in the whole world growing up.

Amy Farrah Fowler: Really? Why have I never heard you mention him before?

Sheldon Cooper: Oh, of course I have. I’m sure I’ve mentioned him, like, five times this week.

Amy Farrah Fowler: I don’t think you have.

Sheldon Cooper: Tam! Tam! Tam! Tam! Tam! There, it’s only Thursday.

Amy Farrah Fowler: I didn’t just drink the crazy milk, I bought the crazy cow.

From The Big Bang Theory – Season 12 Episode 4: ‘The Tam Turbulence’ (12×04)