* King Brady in the new season: There was never a "new season" of Pair of Kings beyond the initial three. The show ended in 2014. There were no episodes that showed what happened to Brady after the series finale.
* Boomer and the parents: Boomer, the mischievous king's advisor, is alive and well at the end of the series. He and the king's parents, King Ron and Queen Millie, are also alive. They are all happily living on Kinkow.
If you're looking for closure on Brady's future, it's possible that the writers left it intentionally open-ended to let viewers imagine their own conclusions.