The supermodel, who has one daughter, is pregnant with her fianc 's child

By Rebecca Paley Bryan Alexander
March 16, 2005 12:00 PM

German supermodel Heidi Klum is expecting a baby with her fianc , British pop star Seal, PEOPLE has confirmed.

Sources confirm that the couple’s new baby is due in the fall. “They are thrilled,” says a pal. “They have created a nontraditional family unit.”

That family includes Klum’s 10-month-old daughter, Leni, whose father is 54-year-old Italian businessman Flavio Briatore. But from the beginning of Seal and Klum’s romance – which began in February 2004 before Klum gave birth – the singer has taken up fatherly duties for his fianc e’s little girl.

Seal prides himself on playing the proud papa – from celebrating with champagne at the New York City hospital where Klum, 31, gave birth last May to dedicating his latest album, Best: 1991-2004, first to “my daughter Leni,” then to Klum and her parents. Says a pal: “He is crazy about Leni, he is always carrying her around. He is the first one to change a diaper.”

“What I love most about fatherhood,” says Seal, 42, about caring for Leni, is “the opportunity to be a part of the development process of a new life.”

The never married singer – who has no other children – is obviously committed: The day before Christmas Eve he proposed to Klum atop a Canadian mountain, and the couple have purchased a $4.3 million Bel-Air estate.

In a statement released by the couple on Friday, March 18, they said of Klum’s pregnancy: “There is nothing that gives us greater happiness than the realization of our dream.”

And when will they finally seal the deal? “I would say they’ll be married within a couple of months,” says a source. “He takes it very seriously. Heidi and the baby come first.” Make that the babies.