Heidi Klum Reveals The Secret Behind Her Successful Marriage

Heidi Klum says a deep love keeps her marriage to Seal strong.

The supermodel - who wed the 'Kiss from a Rose' singer three years ago - has stressed the importance of love and believes it is vital to a happy relationship.

She said: "There are many, many things. But I would say love is the most important thing."

Heidi - who has two children, two-year-old Henry and 19-month-old Johan, with husband Seal and a four-year-old daughter Leni from a previous relationship - recently revealed she wants to extend her family.

She said: "So many people say, 'I am so done.' That hasn't come out of my mouth, and it hasn't come out of Seal's mouth, either. I feel like we still have one coming."

The 34-year-old beauty also said she considers Seal to be Leni's real father, even though Formula One team boss Flavio Briatore is her biological father.

She added: "Seal is Leni's father. Seal and I feel very lucky that we found each other. He's my best friend. He would never go in through a door first. He always opens the door for me and steps back so I walk through."