Frontier Gal is a Western movie from 1945, directed by Charles Lamont.
The spanking scenes
The first scene
Johnny Hart (Rod Cameron) has been released from a six-year prison sentence and learns he has a daughter, Mary Ann (Beverly Simmons). He wants to raise her himself because her mother Lorena Dumont (Yvonne De Carlo) owns a saloon and he doesn't want his daughter to grow up in a saloon. He takes his daughter to his place, where she demands to be instantly taken back to her mom. She throws a tantrum and misbehaves as much as she can, kicking Johnny's shin, breaking things and throwing objects at him. Johnny remains very calm and self-controlled, merely protects himself, and tries to reason with her, but no avail. Finally he chases and gets hold of the girl. He takes a seat and puts her sideways across his lap, where he spanks her six times on the seat of her dress, then puts her on her feet again. Mary Ann sobs a little ("You spanked me!"), but then remembers that "fathers spank little girls because they love them... Oh gosh... You love me." At this, Johnny sits her on his lap and hugs her.
The second scene
In the second spanking scene, Johnny takes Lorena over his lap and spanks her while Mary Ann stands aside and watches. Mary Ann then remarks "You gave mommy a good spanking." He says "That's because it was necessary," and the girl replies "And because you love her." He says that it is true, and Lorena finally realizes he actually loves her. She gets up and the two make up with a kiss.