Is it Okay to have the boys play in water sprinklers, instead of swimming, during the nine days?
It’s Okay to have the boys play in water sprinklers during the nine days, if effort is made that only face hands and feet become wet, or in the alternative only a minority of the body.
משנ״ב תקנא, צד.
והארכנו במק״א בדין רחיצה לקטנים בתשעת הימים. ואכ״מ. וראה משנ״ב סקצ״ג.