Japanese tennis bros, 4 and 6, are already acing it
Japanese tennis bros, 4 and 6, are already acing it

These tots are "twinning" the tennis game.

Watch siblings Yu and Ko Kosuke, ages 6 and 4, show off their sporty skills in Fukuoka, Japan.

Their adorable athleticism has caught the eye of tennis coach Judy Murray — Andy Murray's mom.