The 'Rosemary's Baby' actress - who has four biological and five adopted kids from her marriages to composer Andre Previn and director Woody Allen - admits the crooner, who she was married for less than two years between 1966 and 1968, was the great love of her life and she continued sleeping with him long after they separated.
She admitted: ''We never really split up.''
Asked if Ronan, her only biological child with the filmmaker, could be Sinatra's child, she told Vanity Fair magazine: ''Possibly.''
Although no DNA testing has ever been done on Ronan, now 25, he is treated as a member of the Sinatra family.
Nancy Sinatra Jr., the daughter of the singer - who died aged 82 in 1998 - told the publication in an email: ''He is a big part of us, and we are blessed to have him in our lives.''
In 1992, Mia accused Woody of molesting their daughter Dylan then seven, and sought Sinatra's help in protecting her because she was concerned the filmmaker's alleged connections to criminals in the Teamsters organisation.
The 'My Way' star set up a meeting for her with a Mafioso pal with whom she met in the back of a car, where he told her: ''The Teamsters? Don't worry about it. We own the Teamsters.''
Mia, 68, recalled: ''I remember babbling, 'Thank you, thank you'. Off he went, and I did feel safer.''
Kai Whiston is back already with his second album of his own 'No World As Good As Mine', and this time he has the help of organic instruments.
Her debut album The Witching Hour is out soon.
Feet are mid-tour and promoting their debut album, and tonight they played Ramsgate Music Hall with support from local band Malpractice.
Famed for performing one of her own songs as her opening gambit on The X Factor, Lucy Spraggan rocked up at the Booking Hall as part of her UK and...
After nearly thirty years since his first solo record Mark Lanegan has just released one of his very best and there's not many artists who can claim...
Listen to their new single 'People Change'.
For the first, and almost certainly last, time Cambridge indie rockers Mallory Knox performed at The Booking Hall in Dover.
'Devour You' is a fantastic follow up to Starcrawler's debut album and represents a move on in terms of sound and, in part, direction.
Solondz takes another hilariously pitch-black exploration of human behaviour with a film populated by excellent...
Jesse Peretz's stitched-together comedy The Ex casts funny actors and provides funny scenarios but rarely...
My favorite character in John Moore's remake of The Omen is the Pope. I am...