What Causes Nose Bleeds And Blood In Bowels Of A Child?

My 13-year -old grandson has had a respiratory infection this week. Last evening he has two nosebleeds. Early this morning when I went into his room to wake him up, I saw dried blood coming from his left nostril going down his face, & down to under his left ear. Some of it was fresh. The part at his nostril & under his ear looked fresher. He defacated about 2.5 hrs ago. He told me blood came out with his fecal material but poop was normal color. Is this blood from what he swallowed when his nose bled earlier today & last evening? Is that possible? I can schedule a dr visit, but he is not very cooperative with fecal blood testing. I might be able to convince him. Please advise.