Being a godparent is still very much a thing in the Greek Orthodox Church, a couple with the same godparent are not allowed to get married religiously bc that would be « spiritual incest ». So the tradition is one becomes a godparent either to boys only or to girls only.
Also, the tree-splitting thing isn’t that novel, it was also done by a bandit killed by mythological hero Theseus https://en.wikipedia.org/wiki/Sinis_(mythology)