When the triplets turned five, they became very active and rowdy. They were unaware that Phoebe was their surrogate mother until a later episode, where Chandler Bing accidentally reveals it to the triplets, and when they stare at him in bewilderment, he quickly leaves the coffee shop, quipping that he will now "tell Emma she was an accident."
|“||Alice (to Phoebe): Okay, now, see, I wanna name the girl baby Leslie, and Frank wants to name one of the boy babies Frank Jr. Jr.
Chandler: Wouldn't that be Frank the III?
—Alice Buffay and Chandler in "The One With Rachel's New Dress"