He had left Winterfell with the Maester whom he had claimed for his Service and with a couple of northern Guards after spending a good ten days with Stark and some of his Lords.
They made their way southwards to the town Barrowton where he and his Maester stepped onto a boat which brought them to the Saltspear at the Blazewater Bay, where three ships from the Westerlands were waiting for him, ordered for this via Ravens which he had sent from Winterfell to his family during the first few days of his stay there.

It had felt good to step on board of his own ships, to see the sails in his colors, to hear them snapping on the strong wind over his head, to be surrounded by men in his colors and to know that his Power was intact.

Maester Hother and he were involved in a fierce game of Cyvassse when Casterly Rock came into view many days later and Tywin was so enamored by the sight of the proud, skypiercing Mountain that he cared no longer that he was losing his game to his competetive Maester, something which was normally against his Lannister pride.
But no game mattered anymore...

Finally!
Finally he was home again.

...
It took not long anymore from seeing the Rock in all his might to arriving there and to be welcomed then properly by his family and his household. Well, by nearly all his family but for his children...

Even though the Lord Lannister was a bit travel weary, he still ordered to hold no welcoming feast but instead for his siblings to accompany him to his Solar for a much needed conversation.

Maester Hother was brought to the guest quarters till better accommodations would be readied for him.

Many hours later in the Lord's Solar, the oldest Lannister told his siblings what had been done to him and what he had learned from commoners about the fate of their youngest sibling.

"I kill him, I kill this misbegotten piece of shit for what he did", shouted Tygett with raw hate in his voice, while Genna swallows down her tears and Kevan just looked incredibly sad.

"You will do no such thing," came Tywin's sharp and cold reply. "You will do no such thing, for he belongs to me, he is mine to kill and to ruin, just like his father was before him.
Do you understand that Tygett.?" asked Tywin with ice and calmness in his Voice.
His youngest still living brother nodded reluctantly, hate still clearly to see on his handsome face and Tywin decided to be generous and to promise the kill of the second enemy to his murderous minded, hotblooded brother.

"Tygett, I will let you take out your hate on his lapdog Kingsguard Gerold Hightower though, whenever we get him in our hands." Tygett's face lost a bit of the dangerous snarl and he looked a bit more satisfied then while he nodded in agreement.

Kevan's eyes searched for Tywin's at these words and he then carefully uttered his thoughts.
"We are not yet ready for War though Tywin, we need a bit more time to bring all of our own armies, Quellon Greyjoy's Ironborns and the Sellsword companies together here and to..", Kevan could not finish his words, for his older brother had lifted his hand and gestured towards him to stop.

"The North will stand with me, Cersei and Rickard Stark's heir Brandon are betrothed since I had signed the Contract in Winterfell.
The Sellsword companies will be brought to the North, no need for them to be brought to here. And from the North they will make their way southwards, Northerners and Sellswords together, just as we Westermen will come from our lands, we all will meet in the Riverlands and make the way through the Crownlands towards the capital together, all the while the Reavers can have the joy to attack and thus distract the Reachers." declared the Lion Lord in a voice that seemed to accept no contradiction.

"Not that I would doubt your plans Tywin," sighed Kevan carefully, "but for all the good planning, there is one particular embarrassing problem."

The Lord Warden of the West gestured to his brother to explain what kind of problem that would be.

And thus he learned about the misdeeds of his own children...

...
King's Landing...

At the time when Tywin arrived in his Home, the young King readied everything for the arrival of one of the main parts of his future...

The egg laid in a large, blood filled bowl made from granite. This bowl laid in the middle of the fireplace, on and surrounded by white-hot flames. The blood was boiling...
Rhaegar watched it eagerly, his eyes never leaving his egg. Waiting for a change to come, waiting waiting waiting... always waiting...

He would need more blood soon for his precious egg, for the dragon within... more blood because there was not much left in the bowl, it boiled away or it disappeared in other ways and the egg still had not hatched... It was surely still hungry, still not sated...

More blood was needed, more of his blood, more of the old blood of his realm too, all to give strength for his dragon, all to give Power to him, to Rhaegar the Savior of them all...

More blood for more power, for his visions, for his plans to come true.

He emptied a few more cups of relatively freshly drawn blood over the Egg...blood from some of the oldest lines of Westeros...

Sleeping draughts and potions were incredible useful for such necessities to gather thought Rhaegar to himself with a satisfied smirk.
A deep sleep and no-one was any wiser, for a few cuts here and there happened to do many of the young Lords, Knights and Squires during the daily training hours...who could say a day later if a cut from training was opened at night again for a few moments...

Soon, soon Rhaegar promised himself...
Soon...