The Night of the Hunter

In West Virginia in the 1930s, along the Ohio River, Reverend Harry Powell, a serial killer, flees the scene of his latest murder. Powell is a self-anointed preacher with a penchant for switchblade knives, a misogynist who is both attracted to and repulsed by women. He travels rural roads, preaching in small towns, and rationalizes his murders by telling himself that he is punishing sinful women and gaining money to preach God's word. The letters "L-O-V-E" are tattooed on the fingers of his right hand, and the letters "H-A-T-E" on those of his left hand. Powell uses them as symbols in impromptu sermons. In one small town, police arrest Powell for driving a stolen car and he is sentenced to jail.
Meanwhile, a local family man named Ben Harper kills two people in a bank robbery. He arrives home and hides the money he has stolen inside his daughter's rag doll. He convinces his two young children, John and Pearl, to keep the hiding place secret. The police arrive and arrest Ben, while John is shocked by the way the police roughly overpower his father.
Harper and Powell share a cell where Powell, soon to be released, tries without success to learn the location of the stolen money. Harper lets slip enough information to allow Powell to determine that Harper's children must know where the money is. Harper is executed for his crimes, while Powell is released from jail, and then woos and marries Harper's widow, Willa.
Powell charms most of the townsfolk, but John remains distrustful. John does not share the money's hiding place with Powell and must constantly remind his younger and more trusting sister Pearl to maintain the secret. Willa eventually discovers that Powell is searching for the money, though he has earlier denied this to her. Still, the pious Willa believes he married her to show her God's light rather than to gain access to the money. Powell murders her, dumps her body in the river, and covers up her disappearance by claiming she has abandoned him and the children for a life of sin.
With this cover story Powell retains the trust and sympathy of the townsfolk. His position in the town becomes even more secure. Willa's drowned body is discovered by Birdie Steptoe, an elderly man who spends his days drinking on his riverboat and is friendly with John. Birdie keeps his discovery a secret out of fear the town will blame him for her death. Nobody else in town is willing to take John's side against Powell.
Left to care for John and Pearl, Powell threatens their lives and learns the money is hidden inside the doll. The children flee down the river with the doll and take sanctuary with Rachel Cooper, a tough old woman who looks after stray children. Powell tracks them down, but Rachel sees through him and runs him off her property. Powell returns after dark, as he had threatened, and in the ensuing all-night standoff he is wounded by a shot. The police, by now having discovered Willa's body, arrive to arrest Powell. John breaks down as he witnesses the arrest of Powell as a parallel to the arrest of his real father. John takes the doll and beats it against the handcuffed Powell. As the money spills out, he insists that Powell can have the cash if he wants it.
Powell is tried, convicted, and sentenced for his crimes. Several of the townsfolk previously depicted as his staunchest defenders sit in the public gallery drinking and shouting abuse at him. A lynch mob tries to take Powell from the police station but the police retreat with him out the back of the building as the professional executioner promises to see Powell again soon. Finally, John and Pearl have their first Christmas together with Rachel and their new family.

Question: Who discovers Willa's drowned body?
Answer: Birdie Steptoe; Birdie Steptoe