Larry is an imaginative five-year-old boy living in Cork, Ireland. Having spent his early years solely with his mother while his father fought in World War I, he is accustomed to being the absolute center of her world. He is highly protective of his daily routines, views his life in melodramatic terms, and fiercely defends his perceived position in the household against any disruption.

Mother is a practical and stoic homemaker managing tight finances and shifting family dynamics in post-war Ireland. During the war, she forms a close, isolated bond with Larry, but she must quickly pivot to acting as a mediator between her demanding young son and her exhausted husband. She tries to preserve peace in the home while dealing with a loss of income and a subsequent pregnancy.

Mick is a World War I veteran who returns to his family in Ireland needing rest and a civilian job. He is initially awkward and disconnected, struggling to transition from a soldier dealing with the trauma of war to a present father. He is deeply attached to his military souvenirs and frequently seems bewildered by his young son's constant demands for attention.

Sonny is the family's newest addition, born during a time of relative peace following the war. Characterized primarily by his loud volume and constant need for care, his presence drastically shifts the family's priorities. He acts as an equalizing force in the house, forcing both Larry and Mick to adapt to a reality where neither of them is the center of attention.