Dr. Robert Morley is a medical intern who is devastated by his wife’s death during childbirth. Grief Soon hardens into resentment toward his newborn son, and he leaves the child in the care of his aunt Hilda and uncle, then heads off to Europe to continue his medical training.
Six years later, his aunt Hilda visits and brings along his son Billy Morley. The boy grows up believing the aunt and uncle are his parents. He asks his fiancée Martha Morley to have lunch without him, and later he attends his son’s sixth birthday party, enjoying the time with the boy. Martha’s meeting with the aunt and uncle leaves her uneasy about the situation, and after they talk, he opens up about how he lost his wife, leading to a reconciliation between them.
As time goes on, they discuss having children. She makes clear she doesn’t want more, while he believes a child could be a binding bond between them. She suggests bringing Billy to live with them.
He informs the aunt and uncle that he wants the boy to live with him, but they refuse to give up Billy. Dr. Morley takes the matter to court, and Judge Harvey E. Blake grants him full custody. Billy cries, frightened at leaving the only parents he has known.
Billy then moves in with Dr. Morley and his wife, who feels increasingly threatened by the boy’s presence in their home.
Billy works with a tutor to learn French. His father takes an afternoon off to visit the zoo with him. Martha goes out and returns late, admitting she feels left out and promising to try harder with Billy. She buys Billy a small dog, though the gesture backfires when he isn’t happy. The aunts and uncles visit with a cake and the dog he wanted.
Dr. Morley is called away for an emergency operation. Billy hides food to share with the dog, and even lets his monkey into his room. He feeds them cake, and when the tutor finds the monkey, he rushes to fetch the mother. Billy proudly shows her the dog, though the monkey has slipped out the window.
Paul, a suitor for Martha, tells her that Robert has no time for her and urges her to leave him. He even tries to kiss Martha, but she resists; Billy sees the confrontation, steps in, and Paul shoves him, causing a head injury. Robert returns home to find Martha packing. She explains what happened with Paul and says she’s leaving so he can build a life with his son. The doctor tending to Billy later reveals that Martha had donated her blood to save the boy, and Martha realizes she is Billy’s mother and decides to stay.
A year later, they celebrate Billy’s seventh birthday with friends, his dog, and his monkey, marking a quiet, hopeful milestone for a family that has weathered complexity, sacrifice, and reconciliation.
