Whatever age someone dies, they remain that age in the afterlife.
I should reference my old friend Maximus Decimus Meridius who famously said 'What we do in life, echoes in eternity'. I thought about how we would stay the same age we die for eternity... also the injustice of people dying at a young age would be softened if they were to live for eternity at that age.
I lost a cousin who was older than me 4 years ago. Last year I got older than him. In some way, he will always be 20.