The 51-year-old was recently pictured holding his new daughter Mirabella Bunny, who is now three months old.
It's claimed he has denied ever dating Antonia, 36, despite her claims they dated for two years and that he's never owned up to fathering the little girl to her.
The mother of the little girl is Adams' PA Alicia Grimaldi, 31.
One of Antonia's friends said to UK newspaper The Mail on Sunday: 'Bryan has never confirmed to Antonia that the child is even his but we can only assume so.
'He has still never answered a direct question on it. Lots of people believe he would have preferred never to tell the public about the baby.
'Maybe Bryan would have liked to continue seeing Antonia and looking after Alicia and the baby. But he didn't have any choice when it came to Antonia - she refused to see him again after hearing the news.
'They did tentatively speak as friends on many occasions. I believe Antonia had a thought in her mind that it could all go back to normal.'