Kate Hanson and Zac Hanson

Get ready for another Hanson baby.

Zac Hanson, the youngest of the Hanson brothers, and his wife, Kate, are expecting their second child, he announced on the radio show Kidd Kraddick in the Morning Thursday.

"I have a new new baby. It's coming," he said. "Nobody even knows."

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Hanson, 24, and Kate, 26, have been married for four years and have a 2-year-old son, Shephard.

The new addition won't be short of playmates. Oldest Hanson bro Isaac, 29, and wife Nikki, 26, have two sons, Everett, 3, and Monroe, 2, while Taylor Hanson, 27, and wife Natalie, 26, are parents to sons Ezra, 7, River, 3, Viggo, 18 months, and daughter Penelope, 5.