The characters in All My Sons refuse to acknowledge the past. Their denial keeps the old ghosts around with their dirty fingers in everything. Memory of a dead son is inextricably linked, for his parents, to knowledge of a hideous crime. That same dead son's visage puts a stranglehold on his surviving brother's pursuit of happiness with his love, Ann. Characters struggle to suppress these memories but the past works to reveal itself through the arrival of an old neighbor girl, through a telephone call from prison, and through an old letter from the dead son.
Because she possesses Larry's suicide letter, Ann is less burdened by the past than the Kellers.
The neighbors' recollections of past aspirations and failures echo the regret and compromise of the main plot.