Cleopatra confronts Julius Caesar in this 1866 painting. She had been driven from the palace in Alexandria by her brother, Ptolemy XIII, whom she was also supposed to marry.

Grandma's stewing about something her sister said 20 years ago, Uncle Rupert's out teaching the kids about bottle rockets, and no one on dad's side of the family is currently speaking. If your family reunions look something like this, rest easy: You're still doing better than a great number of kings and queens throughout history.

With power and money comes dysfunction, as any number of royal families has proved. From palace assassinations to serial marriages, castle walls have seen it all.

1. Cleopatra, coming at you

Cleopatra is famous for her suicidal ending. What's less known is her bloody beginning — and the familial drama that brought her to power.

After her father's death, Cleopatra's younger brother Ptolemy XIII inherited the throne. She was meant to marry him, inbreeding being one way ancient royal families kept a grip on power. But her ambitions threatened him, and he had her exiled, according to Stacy Schiff's "Cleopatra" (Little, Brown and Company, 2010). So Cleopatra allied with Julius Caesar, retaking the throne with her other younger brother, Ptolemy XIV. That younger brother later died; Cleopatra may have poisoned him. She also had her younger sister Arsinoe IV, another rival, killed in 41 B.C.

Deadly sibling rivalry was common in the Ptolemy dynasty, according to Schiff. The complex family trees occasioned by inbreeding caused succession crisis after succession crisis, typically with deadly results.

"It was rare to find a member of the family who did not liquidate a relative or two," Schiff wrote.

2. Macedonian mayhem

Another surefire way to rile up a royal family is to have lots and lots of wives, all of which would like to see their own children installed on the throne. Alexander the Great's father, Philip II of Macedon, probably had seven wives, including Alexander's mother, Olympias.

Olympias may have had something to do with Philip II's assassination by a bodyguard in 336 B.C., according to some ancient historians, but the truth is fuzzy. According to a later account by the historian Cleitarchus, the bodyguard was a former lover of Philip II, who had taunted the king's new, younger, lover into suicide. Philip II's uncle-in-law allegedly sexually assaulted the bodyguard in retaliation, leading the bodyguard to kill Philip II in his own quest for revenge.

Whatever really happened, the Macedonian family dysfunction did not end with Philip II's generation. Alexander quickly started putting rival family members to death to secure his ascension to the throne, and Olympias had Philip II's last wife and her children killed. After Alexander died in 323 B.C., leaving a pregnant wife but no sure heir, his mentally disabled half-brother Philip III Arrhidaios (also spelled Arrhidaeus) was installed on the throne. Philip III's wife Eurydice attempted to turn this figurehead king into a real ruler; this put her in competition with Olympias in the ensuing wars of succession. Ultimately, Philip III was executed on Olympias' orders, and Eurydice forced to commit suicide. Their bodies were buried and then dug up about 17 months later for a royal cremation and funeral.

Olympias would not escape the succession wars unscathed. Captured not long after she had Philip III and Eurydice killed, she was stoned to death by relatives of people she had ordered executed.

3. Murder of a pharaoh

Harems are all fun and games until somebody gets their throat slit, as Ramesses III learned the hard way. This pharaoh ruled Egypt from 1186 B.C. to about 1156 B.C. — until somebody slashed his neck so deeply that modern archaeologists say he would have died instantly.

Ancient papyrus texts reveal that one of Ramesses III's minor wives, a woman named Tiye, was behind the plot; she was trying to get her son Pentaweret installed on the throne. Dozens of co-conspirators were sentenced to death, according to contemporary records, including Pentaweret. Archaeologists reported in 2012 they may have found the prince's mummy. The corpse in question has an agonized expression and overinflated lungs, consistent with death by suffocation or strangulation. He may have been forced to commit suicide, or he may have been buried alive. [In Photos: The Mummy of Ramesses III]

4. War of brothers

A conflict called the War of the Two Brothers can signal just one thing — a serious family meltdown. In 1527, the Inca king Huayna Capac died, leaving his kingdom to two of his sons, Atahualpa and Huáscar. (The two men had different mothers, as Inca rulers took multiple wives and concubines.)

Joint rule did not work out so well for the two new kings. By 1529, war broke out. Things got personal: According to Kim MacQuarrie's book "The Last Days of the Incas" (Simon & Schuster, 2008), Atahualpa at one point made a drinking cup out of the skull of one of Huáscar's generals.

The Inca civil war would hurry along the downfall of this civilization. In 1532, Francisco Pizarro's Spanish conquistadors appeared just as Atahualpa was declaring victory over his brother. The conquistadors captured Atahualpa and held him for ransom, though Atahualpa was able to get out an important order to his people: Execute my brother. [10 Epic Battles That Changed History]

Atahualpa wouldn't outlive Huáscar by much. The Spanish executed him in 1533.

5. The passive-aggressive emperor

Ever get the sense Mom and Dad like your brother or sister more? The kids of the Wanli Emperor had no doubt. Wanli, the 13th emperor of China's Ming dynasty, had two official consorts and a great many concubines. His favorite concubine, Lady Zheng, had two sons, one of whom Wanli desperately wanted to follow him on the throne.

But the emperor's ministers wouldn't stand for this son — Wanli's third — as heir. Ultimately, they prevailed, and Wanli was forced to declare his first son by his consort Lady Wang the crown prince. [Gold Treasures Discovered in Ming Dynasty Tomb (Photos)]

And then the emperor did something very strange. He stopped working. Wanli had once been a strong ruler, handling internal rebellions and Japanese invasions with panache. The last 20 years or so of his reign, however, were like an extended lame-duck period. In a passive-aggressive protest, Wanli spent decades ignoring meetings, memorandums and all other royal duties, according to a 2011 article in the New York Times. Unsurprisingly, this undermined the country. Many historians attribute the crumbling of the Ming dynasty in 1644 largely to the self-sabotage of Wanli's rule.

6. Captive brother

William the Conqueror, the first Norman king of England, had four sons. One died before him; William split his kingdom for his eldest remaining sons. Robert was given Normandy upon his father's death, and William got the throne of England.

That left the youngest son, Henry. He may not have been granted a kingdom, but Henry knew how to grab an opportunity. In 1100, William the younger died in a hunting accident while Robert was away on a crusade. Within three days, Henry had himself crowned king of England (as Henry I), beating his absent brother to the punch, according to the official histories of the British monarchy.

Robert attempted to take England for himself, but Henry I beat him back — and then, a few years later, took Normandy, too. Robert was captured, and Henry I kept him imprisoned for the rest of his life.

7. A murder mystery

Richard III, the last Plantagenet king of England, was recently exhumed from underneath a parking lot in Leicester. The occasion was heralded by Richard's fans as an opportunity to better understand a king remembered mostly as a Shakespearian villain. But questions remain about Richard's rise to power.

When King Edward IV died in 1483, he left behind two young sons. The eldest, Edward V, was only 12, so Richard III was declared his protector. After a 68-day reign, Edward and his younger brother Richard of Shrewsbury were sent to the Tower of London and then were never heard from again. Meanwhile, Richard III took the throne.

No one knows what happened to the boys, now known as "the Princes in the Tower." A widespread theory holds that Richard III had them murdered. But no one has ever found definitive proof of the princes' deaths (though two small skeletons were excavated from the tower in 1674), and Richard himself died in battle only two years later, taking his secrets to his hastily dug grave.

8. The many wives of Henry VIII

Divorced, beheaded, died. Divorced, beheaded, survived.

Those were the fates of Henry VIII's six wives. Family matters came to dominate the reign of this Tudor king, who could not seem to secure himself a male heir. Originally, Henry married Catherine of Aragon, his brother's widow. When the king's eye roved to the witty Anne Boleyn in the 1520s, his argument for divorce focused largely on whether Catherine had ever had sex with his brother.

The divorce case rocked the Catholic Church, triggering the English Reformation. Henry got his divorce, but Anne proved no more able to produce sons than Catherine (some modern physicians suspect that Henry may have had a genetic disorder that caused his wives' many miscarriages). She was executed on trumped-up charges of treason, adultery and incest, accused of sleeping with her own brother.

Henry would go on to marry four more times and would have one more of his wives, Catherine Howard, killed for adultery. Ultimately, Henry's efforts to install a son on the throne were for naught; his one male heir died as a teenager, only about six years into his reign. Henry's great-niece Lady Jane Grey then took the crown for a mere nine days before being overthrown by his daughter by Catherine of Aragon, Mary I. After Mary I died five years into her reign, Anne Boleyn's daughter Elizabeth I ruled. Her reign was marked by tumult, but Henry's fear that a woman could not hold the throne of England turned out to be quite unfounded: According to the official history of the British Monarchy, the "Virgin Queen" was extremely popular, and the date of her accession to the throne became a national holiday.

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