Hi doctors, my dad had 2 strokes i 1 day, first was 4am then swcond was 10am but we discovered that he had a blood in his brief. what it means?

Hard to tell.: The blood on the briefs might have come from the bowel or the kidneys or bladder. Causes could be infection, diverticulitis, colitis, or tumor. If the strokes were shown to be ordinary ischemic strokes from clots or bleeding there is probably no relationship. If there is evidence of a tumor cause then there could be spread from somewhere else, like a tumor from bowel or kidney. Talk to his doctor.