-This Is an updated version because old one doesn't make sense!!!-

--Jupiter and Planet x, They both are very good friends. Though, Planet x likes Jupiter, Jupiter can not return his feelings as he loves Saturn.--

-One day in the kuiper belt. Saturn found out that Planet x, Tried flirting with his husband. Saturn banished Planet x from the solar system. Since then, Planet X is somewhere... We will never know...-

Till one day, Particularly 4.3 million years later, Planet x, He returned.

((Saturn and Jupiter are married now, they have a son called "earth"))