Palpatine thought of his son as just another asset, a tool at his disposal among the many he had collected over the years as Darth Sidious of the Sith Order, to be put in place and used when necessary. It took several decades, but the time finally came when Palpatine's interests in the Skywalker family line collided at Cloud City.
You see, Lando Calrissian was Palpatine's son.
You might be forgiven for never having made the connection. Lando himself might be forgiven, too, if he forgot, since Palpatine was at best a distant father, a neglectful one. At worst, he didn't exist at all in his son's life, and there was no practical way to even have the connection acknowledged. Except when it suited Palpatine, who was also known as leader of the Galactic Empire, the Emperor. This might be part of the reason why Lando prided himself in keeping Bespin as a whole out of Imperial affairs.
It was his aide Lobot who whispered in his ear, simple as that, upon Darth Vader's arrival, that things were about to become interesting. In other words, Lando should start paying attention, take a personal interest in what was about to happen. If his father had known him at all, he would never have questioned Lando on that score. Lando was a professional, a smooth operator. He had sown his wild oats years ago, during which time he'd come to know a smuggler and all-around rogue named Han Solo.
It was with great reluctance that Lando realized that his old buddy was part of these events. For all intents and purposes, he had to make it look like Han was in fact his only interest in the affairs to follow.
They'd met at the Imperial Academy, where Han had first earned the military distinction that allowed him to captain his own starships after quickly leaving the fleet itself behind. Lando himself had performed his expected service and left it far behind, something he only wanted to forget, but Han made that difficult, a constant reminder, but at least one that allowed him to put it in a different context. His stint in the Imperial fleet had been to that point the only link he'd allowed himself to his father's business.
He'd lost a favored ship to Han in a bet some years previous, and on that basis allowed himself to present a hostile edge between them once Han and his party arrived. It was all Lando could do to avoid thinking about his own problems. As things developed, he was sorry to learn that Vader wanted to use Han as an test subject in human carbonation freeze, just another pawn in a galaxy full of them. Vader was more interested in his own son, Luke Skywalker, who at that point didn't even know they were family. Lando could sympathize.
Events continued to unfold, one small tragedy after another. But the Cloud City affair was the one he finally couldn't forgive, much less overlook. To be neglected his whole life was one thing, but to then be called upon, and not even personally, to ensure that someone else's son would have his life ruined, convinced Lando to choose sides. He'd never taken with the cause of the Rebellion for the shear reason that he didn't think it could succeed.
But now he had reason to support it. When Lando played, he played to win. He hated losing. And he happened to be very good at winning. It was what he'd had to do all his life, to make it bearable. To help him escape.
That was why he sent a message one day to his father, asking him to overlook the final work in the construction of the second Death Star. Bespin had a hand in the work. Did his father know or care what Lando was up to? Probably not. But it was apathy that would finally prove fatal. Lando had volunteered to lead the assault on this second Death Star. He meant to finally have his revenge.
Everything had led to this moment. Everything had to unfold perfectly. Han had his part. Luke had his part. And there was Lando, by all appearances just another weapon in the Rebellion's arsenal. When he flew into the heart of the gigantic weapon, he half-expected for it to be the last thing he ever did.
But it wasn't. As he later heard it, Luke had succeeded in overcoming both Vader and the Emperor. Han had won the heart of his true love and at last found his own lasting peace. But it was Lando Calrissian who blew up the Death Star and thus forever ended the sorry life of Palpatine, bastard father and manipulator of worlds.
But not his son.