28. Sean Astin
For much of his childhood, Sean Astin believed actor John Astin (from The Addams Family) was his biological father after Patty Duke’s affair story. At 14, Patty revealed his real father was Desi Arnaz Jr., who was only 17 at the time.
The paternity secret shattered family narratives quietly. Paparazzi followed Hollywood lineages but missed this bombshell rewrite of his early identity.
