Small town in the old west. Sick child has a bad fever. He (or she) starts to go into convulsions. Townspeople don’t know what to do. Indian grabs child, runs outside and dunks him (her) in the water trough, bringing down the fever and ending the convulsions. Townspeople think the crazy indian was trying to kill/hurt the child and get ready to beat him up/lynch him. Hero/doctor arrives and gives the indian the props he deserves for saving the kid’s life.
I have a vague memory that it’s a Clint Eastwood movie. But it could just as easily be an episode of The Rifleman or Bonanza.
It was Gunsmoke. Festus tried to bring the old Indian back to his tribe, only to discover that the old man had been given the prairie equivalent of being abandoned on an ice floe, and we all learned a hard lesson in multiculturalism.