Disclaimer: I don't own a Song of Ice and Fire/Game of Thrones

Okay this is my first story of the series A Song of Ice and Fire and it will be a mixture of the books and the TV show. Now this story stems from the idea, what if Robert and Cersei had a legitimate son and how would his presence affect the Game of Thrones?

Summary: The only child of Robert Baratheon & Cersei Lannister, Steffon Baratheon, he is the younger brother of Joffrey and older brother to Myrcella and Tommen. From the moment Steffon Baratheon enters Winterfell for the first time after Jon Arryn's death his loyalty, honour and beliefs will be put to the tests. Which side will he join? Will he stay with the Lannisters, or try and restore the pride of the Baratheon house? What about the Starks... Will he give them his allegiance?

Character Ages:

Ned, Robert, Cersei, Catelyn etc: Aged three years from the book.

Theon: 22 Years Old

Robb & Jon: 17 Years Old.

Joffrey: 15 Years Old.

Sansa & Steffon: 14 Years Old.

Arya: 12 Years Old.

Myrcella: 11 Years Old.

Bran & Tommen: 10 Years Old.

Rickon: 6 Years Old.

All characters in this story are aged 3 years from the books. It has been 12 years since the Greyjoy Rebellion and the summer increases by three years.

Steffon looks very similar to Gendry so If you need to picture him, think of Joe Dempsie who plays Gendry in the TV show.

Chapter 1 – Steffon Baratheon

It had over a month of slow riding for the son of Robert Baratheon and Cersei Lannister but he was finally at the last hurdle. It wouldn't be long now until he, and the rest of the assembly, arrived at Winterfell. It hadn't been long since the tragic death of Jon Arryn, the Hand of the King, and immediately his father began preparations to head to Winterfell in order to recruit Lord Eddard Stark to take the place of Jon Arryn. His father had told him many tales of his adventures with the Lord of Winterfell and Steffon couldn't help but admire the man that he had heard about.

Steffon was the second oldest child of Robert and Cersei at fourteen years of age, only a year younger than his older brother Joffrey. He was only a few inches shorter than Joffrey but unlike the thin frame Joffrey had, Steffon had broader shoulders and more muscle on his arms, chest and legs. He also inherited his father's blue eyes. Out of all of Robert's children, Steffon was the only one that had both black and short hair. His uncle Renly would always remind him of how much he looked like a younger version of Robert, just not as large and strong but more fluid and quick. Joffrey, Myrcella and Tommen all had their mother's long blonde hair and green eyes.

A gruff grunt from his right caught his attention and he glanced at his father, who was looking thoroughly bored at the pace they were traveling at. The man that had killed Rhaegar Targaryen, the man that could wield his war hammer with only one hand, when most men couldn't hold it with both hands, no longer existed. In his place was a large man that needed to grow a large beard to cover up his multiple chins.

Steffon and his father had a solid relationship, it wasn't the most loving relationship but it was far better than the King had with the rest of his children. While Steffon was eager to train and he enjoyed fighting, Steffon wasn't interested in whoring and drinking like his father was. In fact, while most believed that he had already lost his virginity to some random whore, the truth was that his virginity was still intact. Seeing his father sleeping around with other woman and cheating on his wife disgusted Steffon. The young Baratheon vowed that he would lose his virginity to his wife and that she would be the only woman that he would have relations with.

Speaking of his mother, the relationship they had was confusing to say the least. Back when he was younger, there were times where his mother seemed to love and adore him, others where she treated him indifferently and in some extreme times, she seemed to detest him. He often wondered if it was because he looked so much like his father unlike the rest of his siblings. His mother and father didn't exactly have the most loving relationship... okay they hated each other. So he couldn't help but assume that some of that hate she had for his father was passed onto him. His theory seemed to be quite accurate considering that she adore her other children, especially Joffrey. It also probably didn't help that Steffon was quite close to Tyrion who his mother detested with a passion. However over the last couple of few years, any affection that she had for him, vanished. There was no doubt why this was. On his thirteenth name day, Steffon won the squire tourney and had been knighted by his father. Suddenly murmurs rose at how much better it would be for Steffon to be the Crowned Prince instead of Joffrey reached her ears and it hadn't pleased her. His father announcing that he would have preferred Steffon to have been born first loudly at the feast the night he won the tourney didn't help matters. Still, Steffon couldn't just blame his mother for the turn in their relationship, he broke it completely when he decided to continuously taunt his older brother at how poor a fighter he was and how shit a King he would be.

The relationship between Steffon and Joffrey was much clearer than the one that Steffon had with his parents from the get go. Ever since they were old enough to understand emotions, they detested each other. Steffon was everything that Joffrey wasn't... he was stronger, smarter and more importantly in Joffrey's eyes, he had their father's approval. To Steffon, Joffrey was nothing more than an arrogant twit who had no skill with a sword, no intelligence and fought using a crossbow like a coward. It wouldn't be so bad if he used a longbow which took much more skill to use and that if he needed to he could wield a sword effectively. However he could easily tolerate that but what really pissed Steffon off was Joffrey's cruelty towards Myrcella and Tommen and in general.

Steffon loved his younger brother and sister deeply and he did his best to keep them away from Joffrey's violence.

The young Baratheon glanced back towards the royal carriage that held his mother and his siblings, including the Crowned Prince. On a black horse not far from the carriage dressed in golden armour and a white cloak that all Kingsguard members wore was his uncle Jaime... the king slayer. He and Steffon only really bonded on the training grounds but outside of sword play, Jaime was arrogant and he never took anything seriously. He reminded Steffon of Joffrey too much for them to have a good relationship. Also he didn't really understand how he could still be a Kingsguard when he was known as a king slayer despite the circumstances that made him choose to kill the 'Mad' King.

His relationship with his uncle Tyrion on the other hand was the strongest out of all of his Lannister relatives, possibly the strongest out of all his relatives. It was Tyrion that had taught him how to read and write. It was Tyrion who told him about the dangers of the court and how they were more deadly than fighting someone on a battlefield. It was Tyrion who would comfort him when he was younger after the times when he believed that his mother detested him. He respected his beloved uncle so much that he would snap at anyone that dared address him with names such as 'Imp' or 'Dwarf' and other names similar.

Steffon hadn't seen much of his grandfather, Tywin Lannister since he spent most of his time at Casterly Rock. However from the little he had seen him, Steffon felt intimidated by him. He radiated a presence that Steffon had never felt from another man, not even from his own father, the King. Just standing near his grandfather made Steffon believe that it was Tywin and not his father that was the King of Westeros. Before he had been knighted, he hadn't even uttered a sentence to his grandfather before but he was summoned to Casterly Rock a month after being knighted. It was a quick visit; he only stayed there for one night before he was off back to Kings Landing. He only met his grandfather once when he was there and it had been the most intense moment of his life. He left Casterly Rock none the wiser on what his grandfather thought of him but he felt that he must have done something to impress him considering he had never talked to his other grandchildren.

Renly Baratheon was his father's youngest brother and Steffon's relationship with him wasn't all that strong. Renly enjoyed the tournaments and festivals along with the games that are played by the small council whilst Steffon preferred learning how to fight and studying history.

Steffon got on a lot better with his uncle Stannis. While Stannis was a cold, stern, strict and humourless man, Steffon didn't know anyone that was more loyal and honourable than Stannis. While Tyrion had taught him about the games that the small council played, it was Stannis that had taught him all about the laws of the kingdom. He was also taught the many different ways to reward and punish those under your command. He had always admired the reward and punishment that he gave to Davos Seaworth. He also taught him how to kill a man. Just a couple days after he had been knighted, Stannis had taken him down to the dungeons and made him execute a man that raped a young boy. He was the only person that Steffon had killed and the young Baratheon could still remember the feeling of his sword slicing through the man's neck. What his uncle said next was something that Steffon would never forget:

"Most men say that you aren't a man until your cock penetrates into a woman but that isn't true. A boy becomes a man when he first kills a man in cold blood. A man will only become a true knight when he fights in a true battle and comes out victorious. So don't allow your new title to inflate your ego, boy. You are no knight yet."

Steffon yearned for the opportunity to prove that he was a knight in battle but currently the world was in peace. While he may want to fight and earn his knighthood, he wouldn't want it to come at the cost of all the innocent lives that get caught up in war.

Steffon also got on well with Stannis's daughter, Shireen as he wasn't the slightest bit freaked out from her condition. His relationship with his uncle Tyrion made it easy for him to overlook her illness.

He considered Jon Arryn like a grandfather. He had been wise, caring and patient with him whenever he was learning sword play or with his education. He still remembered what he had been like a day before he had fallen ill. He had been pale and jumpy and he seemed to mutter under his breath a lot more. The last words that he had heard from the man he considered a grandfather were:

"I'm sorry. I'm so sorry, Steffon. A tough choice is coming for you. I must tell the King the truth. You must be strong!"

Steffon could still remember Jon's face when he said those words. It had been so pale and a lot of sweat was pouring down his forehead and he seemed to struggle to keep his eyes open. He had no idea what Jon was talking about but ever since his death, his words seemed to plague him whenever he tried to sleep.

"This is ridiculous!" King Robert spat furiously which shook Steffon out of his thoughts and he turned to watch his father curse. "We would have been there two bloody weeks ago if it wasn't for that damn carriage and woman!"

Steffon couldn't help but agree with his father. The amount of times they had to stop so his mother could enjoy a meal or having to stop through the night to stay at a hotel or inn was frustrating. Not only that but having the royal carriage meant that instead of their horses jogging towards Winterfell, they were walking.

"It shouldn't be too much farther could it?" Steffon questioned his father hopefully.

"I'm not sure boy." Robert replied gruffly, "It has been so long since I have been up here in the north that I have forgotten the roads. I'll tell you what if I am not there by the end of the day; I swear I will burn that carriage down!"

"Shall we ride on ahead, father?" Steffon asked eagerly.

His father laughed loudly in delight at the suggestion, "I'd love nothing more than to shrug off this boredom and feel the wind on my face once again." The King turned back to his Kingsguard and told them, "Boros, Meryn... My son and I are riding ahead and you are to remain here and help guard that shitty carriage!"

"Yes, your Grace." They both answered.

Father and son eagerly took off down the road and even their horses seemed delighted to be able to run.

"This road looks familiar!" King Robert roared in enjoyment. They could see that the path went up a large hill a few leagues away. "I remember that hill! When we get to the top we will be able to see Winterfell!"

"Shall we have a race father?" Steffon grinned excitedly, "I understand if you don't want to. It would be hard for your horse to keep up with mine since he is carrying around your weight."

"You cheeky brat!" Robert laughed good naturally, "I'll show there is still some life in me yet!"

Unfortunately for Steffon, he didn't take into account that his father's horse was bigger and stronger than his own and his father made sure he knew it when he got to the top of the hill before his son.

Robert's laughter immediately died when he took sight of the Winterfell and Steffon could understand why it caught his father's attention so suddenly. He found it hard to find the words to describe the sight of Winterfell. Kings Landing was a lot bigger and brighter than Winterfell but Steffon felt that you would have better luck breaking through Kings Landing than Winterfell.

"I had been planning on sending you here to be fostered by Ned for a few years." Robert revealed to him solemnly, "There is no better man in the Seven Kingdoms than Ned Stark and he is a much better father than I am."

"Me?" Steffon asked surprised, "If there is no better man than Lord Stark, why not send your heir?"

"I was going to before his fourteenth name day." Robert admitted but then the King snarled furiously and Steffon knew immediately that his father was remembering what happened that day.

"Joffrey has always been a little shit!" Robert spat disgusted, "I can still remember the day when he cut open that cat and showed me the unborn kitten... It was revolting and completely unnecessary. After that I had planned to send him to Winterfell as I knew Ned was the only one that could whip your brother into shape to be fit for a Crowned Prince."

"So you changed your mind after the hunt on his fourteenth name day?" Steffon guessed. He almost brought up the incident involving Rhaegar's children but he decided it wouldn't be worth his father's wrath for bringing it up.

"Yes." Robert hissed furiously, "As you well know, on the fourteenth name day, a special hunt takes place. This is special tradition for all male Baratheons to prove yourself by hunting down a buck and taking it down on your own. Unless you are successful, you can never be considered worthy of being a Baratheon. All those that fail, either die from the power of the buck's antlers or is disinherited. It is rare for any to fail and the only one that I know that did was my great, great uncle. Yet he is still remembered with honour... he had been a sickly child apparently but still tried to kill the buck with a spear. It took immense courage. And what did your older brother do? He shot it with a crossbow!"

Steffon flinched at how loud his father's voice shouted but his father didn't notice and continued his rant.

"My son! The Crowned Prince! Heir to the Iron Throne! Using a fucking crossbow to kill a buck! Disgraceful!" Robert stopped for a moment and considering his heavy breathing and sweat running down his face, Steffon assumed that he had released all the air in his lungs and needed a moment to gain his strength back. "My son is the only Baratheon in history to use a crossbow to kill a buck! Every other Baratheon has used a sword, a war hammer, a spear, an axe and some have used a simple dagger but never a crossbow!"

Steffon could see how much this hurt his father. He knew that his father believed that his ancestors would be all laughing at the fact that he had created the only known Baratheon coward.

"But then you came along my son." Robert said with pride which startled Steffon. His father wasn't one to show much pride for any of his children including him. "You won a tourney at 13 and became a knight. And on your fourteenth named day, you killed a buck by throwing a spear. If you had missed, or hit it in the wrong area, then you probably would have been killed. You had the courage to stare down the buck and then when it charged, your spear went through its heart. It reminded me so much of my own hunt. I can still remember the taste of that buck. From that moment, I wished that you had been born first and that you would be my heir. So I decided that I would send you to learn from Ned until of course, Jon's death changed things."

Steffon felt pity for his father for the first time. He had never seen his father so upset when Jon had died.

"If Lord Stark accepts your request then I could learn from him in Kings Landing." He pointed out hoping to get his father out of his saddened mood.

It seemed to have worked as a grin appeared on his father's face and he boomed, "That's a good point."

Father and son didn't speak anymore as they waited for the rest of the assembly to arrive. Steffon never took his eyes off Winterfell and he had a feeling that everything was going to change once he entered those walls.

End of Chapter

Next Chapter: Robb Stark

From the stories that I have seen that have a true born son of Robert and Cersei, he is always paired with either Sansa or Margaery. So I thought I would try something different and pair him with Arya. At first I thought to just put Gendry as the true born son but I have plans for him in this story, so I had to use an OC.