In an exclusive interview with Vanity Fair for the magazine’s November issue, Mia Farrow suggests for the first time that there’s a possibility her son Ronan, 25, is Frank Sinatra’s boy, and not Woody Allen’s.

Ronan was thought to be Farrow and Allen’s only biological child, explains The Guardian.

In a preview for the issue, Vanity Fair teases:

Farrow discusses her relationship with Frank Sinatra, telling Orth that Sinatra was the great love of her life, and says, “We never really split up.” When asked point-blank if her biological son with Woody Allen, Ronan Farrow, may actually be the son of Frank Sinatra, Farrow answers, “Possibly.” No DNA tests have been done. When Orth asks Nancy Sinatra Jr. about Ronan’s being treated as if he were a member of her family, Sinatra answers in an e-mail, “He is a big part of us, and we are blessed to have him in our lives.” [Vanity Fair]

Though it’s been rumored to be the case for years, reports New York Post’s Page Six, this interview is the first time that Mia publicly admits the possibility. Farrow and Sinatra were married for all of two years, from 1966 to 1968, but continued to be involved afterwards, even as Farrow got together with Allen. Sinatra, who died in 1998, would have been 78 at the time of Ronan’s conception, adds The Guardian.

The Washington Post also finds a resemblance between Ol’ Blue Eyes and Ronan, a human rights lawyer who frequently accompanies his activist mother around the world in her endeavors as a UNICEF ambassador.