Nose bleeds common
Most of the time nose bleeds
in kids are due to dry air +/- nose picking or rubbing, and not letting the fragile skin
in the nose heal between insults.
Preventive- try vaseline or neosporin to lining of nose.
Try with next bleed: have him blow nose fully to get out clots + mucous, hold nose firmly just below the hard part for 5min (don't tip head back), then if stopped-don't touch!