Magnani had a love affair with the actor Massimo Serato, by whom she had her only child, a son named Luca, who was born on 29 October 1942 in Rome, after her separation from Alessandrini. At the age of 18 months, Luca contracted polio and subsequently lost the use of his legs due to paralysis. As a result, Magnani spent most of her early earnings for specialists and hospitals. After once seeing a legless war veteran drag himself along the sidewalk, she said, "I realize now that it's worse when they grow up", and resolved to earn enough to "shield him forever from want".