Plus: Ellen Pompeo has to explain what a “pick-me girl” is to Heigl.

When they met, they were grunts… nobodies… the bottom of the surgical food chain.

But look at them now.

Katherine Heigl and Jeffrey Dean Morgan on ‘Grey’s Anatomy’

Katherine Heigl and Jeffrey Dean Morgan on ‘Grey’s Anatomy’.Scott Garfield/ABC/Getty

Heigl remembered a young fan stopping her recently and asking if she… played Izzie’s mom?!

But there’s one scene in particular that they both remember.

Pompeo was the first to say it: the ghost sex.

There’s a few that I’d be like, ‘Maybe we fast-forward through this moment.'"

POMPEO:“The sex with the ghost.”

HEIGL:“Yeah that.

Maybe the like oral sex with the ghost while somebody else was watching in the room.

I don’t know how I explain that.”

We couldn’t have said it better ourselves.

Watch Heigl and Pompeo’sfull conversation here.