There are now 103 living best actor and best actress Academy Award
winners. Eight are younger than Casey Affleck, 41, and two (Brie
Larson and Jennifer Lawrence) are younger than Emma Stone, 28. The
oldest winner is Olivia de Havilland at 100. The oldest best actor
winner is Sidney Poitier at 90.
It is quite common for the best actor winner to be more than a decade
older than the best actress winner in the same year, but the reverse
isn't exactly rare - see Eddie Redmayne and Julianne Moore, for
example, in 2015.
The earliest award year with both recipients surviving is 1972 - Gene
Hackman and Jane Fonda. The most recent award year with neither
surviving recipient is 1982, when Henry Fonda and Katharine Hepburn
won. The most recent award year with one surviving recipient is 2006,
the year the late Philip Seymour Hoffman won best actor.
The most recent death is Luise Rainier in 2014.
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