De-seriously?

“Yes brother,” says Paddy.
“Well I’m going on a business trip soon and if she gives birth while I’m away, I want you dear brother, to name the kids,” says Mick.
“It’ll be an honour to do that for you Mick,” says Paddy.
A month later Paddy calls Mick.
“Hello Mick, your wife’s given birth to a boy and a girl, they’re beautiful,” says Paddy.
“That’s wonderful Paddy, what did you call them?” says Mick.
“I called the girl Deniece,” says Paddy.
“And what did you call the boy?”
“I called the boy De nephew.”