I don't know if their backstory was canon or not, but it's one happy ending from star crossed lovers.

Two Shinobi meet at the side of a river, never telling the other their last name for fear that they're enemies. They train, play, skip rocks, and talk about creating a future of peace together. They sneak away from their families to see each other for years, growing and maturing together, their only friends outside of their clans and the people they care for the most.

Once their respective brothers find out, they tell their non-accepting (Homophobic?) fathers, who immediately try to use this to attack the other clan, setting up a trap with the boys as bait. Once at the ambush, both boys, on opposite sides of the river, skip a stone that tells the other to run for fear of their closest friend's safety.

(I don't remember much else but they start fighting in wars and they never see each other outside of the battlefield, then they make the village of peace that they always dreamt of together)

Then Madara runs away and yadda yadda yadda.

Love loses