Sportsman's Double

I met an older woman at a bar last night.

She wasn't bad for 57, we drank and bullshitted a bit,
then she asked if I'd ever had the 'sportsman's double',
a mother and daughter threesome?

I said no.

We drank a bit more,
then she says that tonight was my lucky night.

I went back to her place.
She put the hall light on and shouted upstairs:
"Mom, you still awake?"