Los Angeles - Decades of rumors have been swept aside as a formal DNA request seeks to verify if the Repulsion/Rosemary's Baby/Frantic director is indeed Ms Dobson's birth father.
The former Eastenders actress and sometime Strictly Come Dancing contestant bears an uncanny resemblance to the Polish/French movie man.
Last week a bequest in a UK woman's will was made conditional on Dobson's paternity proof - something that the actress has long been coy about.
"She stands to inherit around two million squid," the editor of celebwatch website LA FagHagSlagMag.con said today.
"Apparently it all goes back to a deal brokered by ex-US President Richard Nixon in highly iffy negotiations with Watergate scandal priests."
Dobson, 63, is married to Queen guitarist Brian May, long rumored to be the secret brat of Elizabeth Windsor and a major British property fraudster who sold-on his ill-gotten London estate to one of Colonel Gaddafi's sons.
At her Slurry - er...Surrey! - home today Dobson was staying tight-lipped as reporters clamored for her reaction to the LA lawsuit.
Meanwhile at an offshore bank somewhere in the Caymans former UK Prime Monster Tony B Liar was busy drawing his ten per cent commission, utterly confident that elder sister Anita won't be subject to the intrusive DNA swab.
Some years back Blair was surprisingly successful in imposing legal gags on anyone even hinting that Victoria Beckham 'is Cabaret star Joel Grey's daughter'.
His son David Beckham's birth mother Anji Hunter is 69.