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?