dave lopez spoke with devastated family members. >> we're just trying figure out what's going on with this country. >> reporter: a grief-stricken grandfather robert priest, sr., reacting to the stabbing death of his 24-year-old grandson jonathan denver. >> i guess this was a father- son outing? >> they had planned it for a week. >> reporter: it was to be a special father and two sons outing for a very good reason. >> today's my brother's birthday. >> reporter: it was a birthday trip? >> yeah. >> reporter: jonathan, his brother robert, and their dad robert priest, who also works as a security guard at dodger stadium, made the special trip to the giants-dodgers game last night to celebrate their dad's 49th birthday. the family said they had a great time at the game and then they were walking back to their car. >> all i know is that they were walking back to their vehicle. they were going to get into their vehicle, a giants fan made a comment, comments were exchanged. and an altercation broke out. >> you said your brother is not the kind that would want to fight back? >> none of them wer