Oscar-winning actress Reese Witherspoon appeared on the Late Show with David Letterman last night.
At one point, David showed the audience a picture of Reese with her 15-year-old daughter, Ava.
(Here's the picture he showed BTW).
After looking at the pic, Reese mentioned how Ava was born the same year she first appeared on Dave's show.
There's silence — Dave realizes he's got a good joke on his hands.
He goes in for the kill...
And Reese finally figures out what's going on.
Don't worry, Reese — we've all been there.
Spoken like a true Elle Woods!
You can watch the whole hilarious moment here.
