My boyfriend just saw his dad die in his arms. What do I do?

His dad passed away due to cancer. He's gone completely non-verbal and doesn't even react to anyone's presence... I have no idea as to what to do. I don't know if he wants me to be there, I don't know if he wants me to leave him alone... Feels like whatever I do will be wrong.

EDIT: Thank you, everyone. I stayed up with him all night, bringing him some food and water, and a few hours ago he finally talked for the first time since his dad passed. Just a "thank you" after I told him I wouldn't leave him alone unless he wanted me to.

I'll see what I can do to help him more; ask his family to help out with the paperwork so he doesn't have to worry about that, figure out what his comfort food is and make that for him, and be there all the time. I'm going to stay at his place for a few days, or at least until he tells me to leave if he chooses to do that, to make sure he's doing as well as someone in his situation could be.

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