United Kingdom, Aug. 3 -- Heidi Klum was shocked when her son decided to be a model.

The supermodel's son Henry, 19, was initially set on a music career like his famous father Seal but surprised Heidi by deciding to follow her onto the runway.

She told HELLO! Magazine: "I always thought he was more into music, but he came to me and said he really wanted to give modelling a shot. I've been there for him a little more because it's new to him."

Heidi's daughter Leni, 20 - from a previous relationship with Flavio Briatore - is also a model and Heidi has encouraged her children to stand up for themselves in such a tough industry.

She said: "Leni is doing so well. She's incredibly but she always knows I'm there for advice.

"The best advice...