The Scottish rocker has confirmed rumours the leggy blonde had been approached to become a Tv star on the hit Bravo network franchise, but she was not interested.
He tells Tmz.com, "She was asked but she turned it down... She doesn't want to do that sort of thing. She's just happy being a mum."
And the Maggie May hitmaker, who has two young sons with the beauty, insists he had no influence over Lancaster's decision, adding, "Whatever she wants to do, she does. She's an independent woman."
Incidentally, Stewart's grown-up son from a previous relationship, Sean Stewart, is currently dating former Real Housewives castmember Adrienne Maloof.