The singer has been openly critical of the supermodel's new relationship with her bodyguard Martin Kristen, accusing her of "fornicating with the help", and only last week Martin was said to have told Seal to "quit disrespecting Heidi".
But as the new couple stepped out over the weekend, they didn't seem to care who saw them looking very much loved up.
Heidi had brought Martin along to help her support her son as he played a football match in LA and he looked very at home with her brood as they cheered on from the sidelines.
Heidi only confirmed the pair were seeing each other last month, but played down the romance during a US TV appearance.
Asked if she was in a "proper relationship" on Katie Couric's show, she said: "I don't even know if I can call it that. I don't know."
Elsewhere, the model has just been announced as the host of the MTV EMAs.
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