As eldest, K'Grall was expected to become Chancellor in succession of his mother. However, K'Grall wanted to be a warrior fighting the Romulans along such great warriors as Kor, Kang and Koloth. Though he did not succeed his mother as Chancellor, his voice had great influence in the Klingon High Council.
When L'nihilus Nox of Romulus killed Chancellor Azetbur, K'Grall, along with his brothers and sister, swore a blood-oath to hunt Nox down, kill him and, according to Klingon tradition, cut out his heart and eat it. Instead of staying together, for K'Grall believed that they needed no strength in numbers - each of them being more than a match for any hundred Romulans, they spread out across the galaxy, in search of Nox.
K'Grall is somewhat level-headed, and usually has a strategy or two up his sleeve. He is rumored to have slain six Gorn by himself, and keeps their skeletons aboard his Bird-of-Prey's captain's quarters as a war trophy.
The next son chose a humble life in service to the Klingon Empire: the removal of prisoners to Rura Penthe. While there, he encountered the last strain of the Augment virus, and his Klingon ridges were lost along with it. Unfortunately, since the virus had been exterminated throughout every corner of the Empire, the cure had been forgotten.
Because of this, K'holl harbors a great hatred for humans for "defacing" his honor. Forgetting his post on Rura Penthe, he took his Bird-of-Prey to Federation space, attempting to find and destroy the USS Enterprise-B. He was stopped by his brother K'Grall, who told him that it would be dishonorable suicide to go against an enemy this way.
When his mother died, K'holl pledged a blood-oath with his brothers and sister to hunt down the murder, a Romulan by the name of L'nihilus Nox, and kill him. His quest for the Romulan was mostly in Klingon Imperial space, because he believed that Nox would be foolish enough to remain in Imperial space and do more mischief.
Eventually, he joined Kang, Koloth and Kor on their quest to bring the Albino to justice. This led him to the USS Admonitor, where he saw Nox in person. He then sent out a call to his brothers and sister that he had found their quarry. Shortly thereafter, he was called again to Narendra III to witness a duel between his sister and the captain of the USS Enterprise-C. After which duel, he and the other brothers vowed a blood-oath to Edward Shield, whom they greatly respected.
K'holl later came to the infamous Khitomer massacre in order to protect his people from the Romulans. Fortunately, he arrived in time to save his sister from the falling of K'ho Mesa. His last action was during the crash, when Admiral Sanders impaled him through the chest: K'holl responded by doing the same with his bat'leth into the chest of the human admiral. Both died of their fatal wounds.
K'holl is brash, somewhat fool-hardy, and hot-headed at times. However, he is a capable warrior, and those who serve under him or who have known him as an ally attest that he is always true to his word, and takes his honor very seriously (like all Klingons do).
As his name suggests, Gor'kang was named after Kang. He is the twin of Gor'goR. Rather than follow in the steps of some great one, Gor'kang wanted to make a name for himself. Accordingly, he had a vision in his teenage years where Kahless himself told him where to find the legendary Sword of Kahless. The vision also told him exactly where to find it.
Believing this to be a call of destiny, Gor'kang took his Bird-of-Prey and a crew and made for Bajor, where a wormhole to the Gamma Quadrant, the location of the Sword in the vision, was located. He was stopped, however, by the Cardassian space station Terok Nor. He would have killed himself out of shame of not fulfilling the prophecy, but a new chance to regain his honor arose.
The death of his mother at the hand of L'nihilus Nox gave Gor'kang new cause to go into battle. If he could kill the Romulan, his name would be remembered. He set off looking for Nox, and an alternate route into the Gamma Quadrant.
Gor'kang is, in many ways, the exact opposite of his twin brother Gor'goR. Gor'kang is quiet, ruthless and cunning.
The twin brother of Gor'kang, Gor'goR is wanted through the Romulan Star Empire for his brutality against Romulans, some guilty of crimes against the Klingon Empire, some innocent. His anti-Romulan genocidal acts have, so far, been ignored by the Klingon High Council.
When his mother was killed by L'nihilus Nox, Gor'goR swore the blood-oath to kill Nox and avenge their mother. He discovered the location of Nox's pirate coven, and destroyed it along with his sister K'hallA. The two them began pursuing the Kalryhha, Nox's Romulan Warbird, across the galaxy. They managed to engage it seven times, none of which were ever successful.
During an incident where he was separated from K'hallA, Gor'goR shared a vision that his twin brother also had some years ago: a vision where Kahless appeared and told him the location of the fabled Sword of Kahless. Gor'goR knew that his brother would go after it, and so he headed for Bajor, fabled site of the Bajoran wormhole: the passage to the Gamma Quadrant.
Gor'goR is the exact opposite of his twin brother. He is considered the "life" of the party of the five: he is rarely reserved, and sometimes, to his own regret, lets his feelings show before his enemies.
Favored by their uncle T'Krang, K'Ragdha is closest to his sister K'hallA. In an act of admiration for slaying an old blood-enemy, T'Krang named his Bird-of-Prey the IKS K'Rada, homonymous to K'Ragdha's name.
K'Ragdha believed that the Federation could not have lasted as long as they have against the Klingon Empire if they were not worthy foes. This influenced his dealings with them. He never went against Federation ships, even though it met with his uncle's disapproval. This led to some tension between them, which was forgotten in the wake of a personal tragedy: the death of Azetbur by Romulan L'nihilus Nox. K'Ragdha also swore the blood-oath to kill the murderer, and he went his way in search of him.
When K'Raghda received a message from T'Krang, stating that he had found Nox, he turned his ship to their coordinates. He and K'holl reached the site first, but discovered the K'Rada heavily damaged in orbit near Q'kharr. K'holl beamed down and began hunting them, only to return empty-handed. Nox was not with the Starfleet officers on the planet.
Somewhat more level-headed than K'Grall, he is more of the diplomat of the five brothers. Though he relishes battle like any true Klingon, he does not care for the shedding of innocent blood.