What do you say on facebook to friends or family that have lost a loved one? Most people type prayers or sending prayers. I usually post you and your family are in my thoughts.
Gift certificates to a take-out in their area. There are so many things to take care of in those first few days.
And the shock, especially if unexpected may send a person into near debilitating depression.
Maybe offering to pay for house cleaning for awhile.
Visit even though they may be horrible company.
I usually say: Sending positive healing energy. I'll be thinking about you and your family. Hugs!
I say my thoughts are with you at this difficult time. If it is a close friend, I would offer my help in any capacity they might need.