When your king is in check during a game of chess, you still have a chance to defend yourself. You can move the piece to a safer square or you might move other pieces in order to protect it. I reckon that the Spanish king is in check at the moment. But not in checkmate. Nevertheless, something must be done.
I suppose that the king of Spain has three defensive moves in progress. The first one —and the clumsiest and least useful, I think— is a PR campaign within friendly circles which can come across as ostentatious and obsequious. The second move is to present the monarchy as the wagon fort that will protect the unity of Spain. If the monarchy is perceived as useful for a goal shared by many Spaniards, it might save itself. The king’s speech on 3 October 2017 [sanctioning police violence against peaceful Catalan voters during the independence referendum] was not merely about the monarchy protecting Spanish unity, but also about the monarchy using Spanish unity to protect itself.
More often than not, when your king is in check you end up sacrificing a valuable piece to try to stay in the game. And the piece which King Felipe is looking to sacrifice at the moment is his own father, the King Emeritus. They are trying to pin all the graft scandals on Juan Carlos to try to save his son, Felipe. Yet after having sacrificed a piece, your king often remains in check. And by then you have run out of valuable pieces that might be sacrificed.