"Mary and Ethel, who?" another person asks.
And Ella quickly chimes in, dripping with sarcasm, "Mary Schwartz and Ethel Hotchkiss."
The joke being that, at that point in time (the late 1950s), the only "Mary and Ethel" any show biz gathering could mean was Mary Martin and Ethel Merman. Two best friends and arguably the two biggest stars in Broadway history.
The two made history of another sort, when they appeared in 1953 on the live broadcast for a big variety special in honor of Ford's 50th anniversary. For 13 minutes, and with no more props than a couple of chair, the two women simply sang classic songs of the previous 50 years, along with hits from their own legendary careers (legendary at that point, yet remarkably they still had a long way to go, with things like Gypsy, Peter Pan and The Sound of Music, among others, still to come. And both did major productions of Hello, Dolly!.). The segment took on a life of its own and became simply known as "The Medley."
By the way, it's worth noting that though Ethel Merman was famous for originating the starring role in Annie Get Your Gun on Broadway, when the road company toured the country, the star was...Mary Martin. And when the show was done on TV, it was Mary Martin who played it.
Anyway, "The Medley" pretty wonderful. And shows what talent can do even in its simplest form. For a long time, this wasn't available. But here it is.