Mariah to produce a baby duet

Mariah Carey is going to be a mom twice over.

Nick Cannon announced on his radio show Thursday that his wife is expecting twins.

Said Cannon on New York’s 92.3 station: “I haven’t even told my wife I’m doing this so I’m probably gonna get yelled at for not getting permission. … We are having twins!”

Cannon added: “Both babies are healthy, in tiptop shape.”

Carey, 40, and Cannon, 30, have been the subject of a baby watch since they got married after a whirlwind romance two years ago.

A boy-band New Year

New Kids on the Block and Backstreet Boys are bringing their ’90s boy-band magic to Dick Clark’s annual New Year’s Eve TV special.

Producers say the two groups are mashing up to close out 2011 on the ABC special.

The two bands, who have melded their monikers to become NKOTBSB, performed together live for the first time on the Dick Clark-produced American Music Awards last month. The supergroup plans to tour North America together next summer.

Pop singers Ke$ha and Taio Cruz are also set to perform from New York’s Times Square on “Dick Clark’s New Year’s Rockin’ Eve with Ryan Seacrest 2011,” which begins at 10 p.m. on Dec. 31 and ends around 2 a.m. on Jan. 1.

Other performers include Jennifer Hudson, Willow Smith, Ne-Yo, Avril Lavigne and Train.

The birthday bunch

Country singer Freddie Hart is 84. Former talk-show host Phil Donahue is 75. Samuel L. Jackson is 62. Country singer Lee Roy Parnell is 54. Drummer Murph of Dinosaur Jr. is 46. Khrystyne Haje (“Head of the Class”) is 42. Actress Julie Delpy is 41. Singer-guitarist Brett Scallions (Fuel) is 39. Singer Lukas Rossi of Rock Star Supernova is 34.