Episode aired 14 October 1965
MARY ANN: Oh, marshal. it's just me.
MARY ANN: Sweet little warm-hearted girl of the golden west me.
GILLIGAN: Why are you crying, Mary Ann?
HOWELL: Will you have a little drink on me?
HOWELL: Would you like a little drink?
MARY ANN: Oh, dare I say it in front of a stranger?
HOWELL: Well, I'm not a stranger.
HOWELL: I'm a friend of your father's.
MARY ANN: Was.
HOWELL: You mean, he passed over?
MARY ANN: Helped by the Apache.
HOWELL: Well, your mother and me, we were kind of friendly.
MARY ANN: Pushed out by the Cherokee.
HOWELL: Your brother, Tom?
MARY ANN: Sioux.
HOWELL: Your sister, Emily?
MARY ANN: Navajo.
HOWELL: Your dear, sweet, innocent little grandmother?
MARY ANN: Shot by the marshal.
GILLIGAN: Well, you can't win 'em all.
The dialogue doesn't explicitly say the Indians killed anyone, but it strongly implies it. No one would get the impression that the Indians kindly "helped" the settlers pack up and move to a better location.
It's a typical example of 1960s stereotyping--trying to have it both ways. The writers might have learned enough not to label Indians as bloodthirsty killers and scalpers. But they wanted to use that racist idea, so they cloaked it in veiled language and slipped it in.