Siegfried & Roy through the years CIRCA 1970: Photo of Siegfried & Roy (Michael Ochs Archives)
Siegfried & Roy through the years 1977 (Patrice PICOT/Gamma-Rapho via Getty Images)
Siegfried & Roy through the years 1978 (Peter Bischoff/Getty Images)
Siegfried & Roy through the years 1981 (picture alliance/picture alliance via Getty Image)
Siegfried & Roy through the years 1981 (picture alliance/picture alliance via Getty Image)
Siegfried & Roy through the years 1987 - Siegfried, right, and Roy, Las Vegas magicians, pose in New York, June 4, 1987 with their rare white tigers, Neva, left, a female, and Vegas, a male, during a stop at Van Cleef & Arpels jewelry before their departure for Germany. The tigers, who were to be exhibited in Germany disappeared in their rented van Thursday and were recovered hours later in the Bronx Borough of New York City. (Scott McKiernan/ASSOCIATED PRESS)
Siegfried & Roy through the years 1987 (ullstein bild/ullstein bild via Getty Images)
Siegfried & Roy through the years 1989 - Siegfried & Roy, master illusionists, appear on the Radio City Music Hall stage in New York, Sept. 22, 1989, with their opening act of "creatures." Siegfried & Roy's act features rare white tigers and vanishing elephants. (Ed Bailey/ASSOCIATED PRESS)
Siegfried & Roy through the years Siegfried Fischbacher and Roy Horn during Opening Night For "Spamalot" At The Wynn Las Vegas - Arrivals at Wynn Hotel & Casino in Las Vegas, Nevada, United States. (Bruce Glikas/FilmMagic)
Siegfried & Roy through the years (Peter Bischoff/Getty Images)
Siegfried & Roy through the years Siegfried Fischbacher and Roy Horn of Siegfried & Roy (Ron Galella/Ron Galella Collection via Getty)
Siegfried & Roy through the years (Peter Bischoff/Getty Images)
Siegfried & Roy through the years 1991 (Peter Bischoff/Getty Images)
Siegfried & Roy through the years 1993 - Siegfried and Roy in Las Vegas, United States on December 01, 1993. (Alain BENAINOUS/Gamma-Rapho via Getty Images)
Siegfried & Roy through the years 1992 - Exotic animal performers/magician' Siegfried & Roy's Roy Horn, host Jay Leno on November 18, 1992 (NBC/NBCU Photo Bank/NBCUniversal via)
Siegfried & Roy through the years 1995 - Illusionists Siegfried and Roy react after receiving the second annual Liberace Legend Award at a gala benefit at the famed Liberace mansion in Las Vegas, May 17, 1995. The two were honored for their tenure in the world of entertainment, their devotion to wildlife conservation and significant contributions to the community. (Lennox McLendon/ASSOCIATED PRESS)
Siegfried & Roy through the years 1997 - Pictured: (l-r) Siegfried Fischbacher, Roy Horn (Siegfried & Roy) during an interview with host Jay Leno on February 5, 1997 (NBC/NBCU Photo Bank/NBCUniversal via)
Siegfried & Roy through the years 2006 - Magicians Siegfried Fischbacher (L) and Roy Horn arrive at the gala premiere of "The Beatles LOVE by Cirque du Soleil" at The Mirage Hotel & Casino June 30, 2006 in Las Vegas, Nevada. (Ethan Miller/Getty Images)
Siegfried & Roy through the years 2008 - This is a Thursday, June 12, 2008 file photo of Siegfried Fischbacher, left, and Roy Horn, of the illusionist team Siegfried & Roy, as they play with a six-week-old white-striped tiger cub at their Las Vegas home. (Louie Traub/ASSOCIATED PRESS)
Siegfried & Roy through the years 2008 - Siegfried Fischbacher (L) and Roy Horn of the illusionist duo Siegfried & Roy arrive at the after party for the premiere of Bette Midler's new show, "The Showgirl Must Go On" at the Pure Nightclub at Caesars Palace February 20, 2008 in Las Vegas, Nevada. Midler will perform 100 times a year at The Colosseum at Caesars for at least the next two years. (Ethan Miller/Getty Images)
Siegfried & Roy through the years 2009 - Siegfried Fischbacher and Roy Horn celebrate the first birthday of five of their tiger cubs at Siegfried & Roy's Secret Garden & Dolphin Habitat at The Mirage on May 12, 2009 in Las Vegas, Nevada. (Denise Truscello/WireImage)
Siegfried & Roy through the years 2013 - Siegfried Fischbacher and Roy Horn attend The Animal Foundation's 10th annual "Best in Show" at the Orleans Arena on April 28, 2013 in Las Vegas, Nevada. (Denise Truscello/WireImage)
Siegfried & Roy through the years 2014 - Siegfried Fischbacher (L) and Roy Horn attend the 18th annual Keep Memory Alive "Power of Love Gala" benefit for the Cleveland Clinic Lou Ruvo Center for Brain Health honoring Gloria Estefan and Emilio Estefan Jr. at the MGM Grand Garden Arena on April 26, 2014 in Las Vegas, Nevada. (Ethan Miller)
Siegfried & Roy through the years 2015 - Siegfried Fischbacher and Roy Horn celebrate SARMOTI Cubs day with Make-A-Wish Foundation at The Mirage Hotel & Casino on October 22, 2015 in Las Vegas, Nevada. (Denise Truscello/WireImage)
Siegfried & Roy through the years 2016 - Siegfried Fischbacher (L) and Roy Horn speak during Criss Angel's HELP (Heal Every Life Possible) charity event at the Luxor Hotel and Casino benefiting pediatric cancer research and treatment on September 12, 2016 in Las Vegas, Nevada. (Ethan Miller/Getty Images)
