"Today" show host Matt Lauer, 43, wasn't on the NBC morning program on Wednesday morning, but his cooing sidekick, Katie Couric, told viewers that Lauer had a good reason. A son, named Jack Matthew Lauer, was born to the TV host and his Dutch-born model wife, Annette Roque Lauer, 35, on Tuesday in a New York hospital. The baby weighed in at seven pounds, three ounces. Mother and baby are said to be doing "just great," said Couric, whose cheerful announcement was echoed by the show's newscaster, Ann Curry. It is the first child for the Lauers. (His previous marriage, to Nancy Alspaugh, ended in divorce.) The Lauers were married in October of 1998. MSNBC anchor Brian Williams sat in for Lauer on Wednesday, and is expected to remain in Matt's seat for the next few days while, said Couric, "Matt gets used to being a daddy."