Have thought for some time that Saturn would have become a star had it increased it's mass a few times over (maybe absorbing Jupiter). Binary star systems are fairly common out there.
Jupiter is already on the verge of starhood. Jupiter has rings, too, but very faint. Saturn is somewhat smaller, but there is something going on there with those monstrous rings. Maybe the warm spot is due to the planet swallowing a moon not so long ago, but how would the heat migrate to the pole?