Who was Getty and why was he hostile towards Tom?

Question

Near the end of the 2014 film Interstellar, the protagonist's daughter Murph (Jessica Chastain) is in her old room while a man outside yells for her to hurry. The man outside is portrayed by Topher Grace, and the character is identified on IMDb as "Getty". The reason for his urgency seems to be the imminent arrival of Murph's older brother Tom (Casey Affleck). As Tom approaches the house, Getty grabs a tire iron from his own vehicle and appears ready to either defend himself or attack Tom as Murphy comes out of the house, then hugs Tom.

I must have missed something, because I had no idea who Getty was during this scene, having never seen him before. I also don't understand why he would be either afraid of, or hostile to, Tom. There was a bad spot on the DVD, however, so I had to skip a chapter - that might explain the gap.

Who is Getty, and why the hostility towards Tom?

Answer 1

There isn't really much more to him other than simply being Murph's friend, possible boyfriend even, a doctor. He seems to work with her at NASA. This is pretty much all we know about him.

He is, however, introduced a little bit earlier in the movie. He is the doctor that cares for the dieing Professor Brand in the scene where he utters his last words. And in the movie's screenplay, as published in Interstellar: The Complete Sceenplay With Selected Storyboards, he is introduced as exactly that:

INT. CORRIDOR, NASA – NIGHT 161

Murph hurries down a corridor with a doctor, GETTY.

GETTY
He started asking for you after he came to, but we couldn’t raise you –

INT. HOSPITAL ROOM, NASA – MOMENTS LATER 162

Murph is at Professor Brand’s bedside. He is hooked up to machines. Barely breathing.

He also appears again later when he drives in the car together with Murph when they go to Tom's house for him to take a look at Tom's son, as he is a doctor. You might have missed those two scenes (or at least his longer appearance in the car and Tom's house) if you really saw him the first time at the very end of the film.

As to why he poses as seemingly hostile towards Tom, that is just because he expects Tom to not be happy with what Murph does. After Tom refuses to move away underground with them or to even let his son be checked by a doctor, Murph and Getty decide to take Tom's wife and son with them for the benefit of their health, which is why Murph lights the fields on fire to distract him. That is why Getty makes himself ready to defend against the returning Tom's rage, who already got violent over this earlier when he punched Getty simply for checking on his son.