What was Brutus's real relationship with Julius Ceasar? Nephew or not?

http://history.answers.com/men/why-did-brutus-assassinate-julius-caesar

Hi,

I’m not sure which sources to believe. I’ve read that Barcus Junius Brutus was Gaius Julius Caesar’s nephew. But other sources call Brutus a friend.

I look forward to your feedback.
davidmich

http://history.answers.com/men/why-did-brutus-assassinate-julius-caesar

March of 44 B.C., a group of Roman Senators led by Gaius Cassius Longinus and Marcus Junius Brutus, a beloved nephew of Julius, stabbed Julius Caesar to death in the Republican Senate.

Caesar wed his third wife, Calpurnia, in 59 B.C., when she was a teenager, and remained married to her until his death. A noted womanizer, he also had multiple mistresses, including Cleopatra VII, the Egyptian queen, and a woman named Servilia, whose son Marcus Brutus took part in Caesar’s murder in 44 B.C.

I don’t see how they could be closely related, since we know the names of Julius Caesar’s parents and of Brutus’s parents, and most of the grandparents, and they don’t share family names. Maybe “Nephew” is code for “I slept with your mom, but we’re cool.”

Brutus was the son of Caesar’s mistress Servilia Caepionis. I think the term uncle in this case is an informal appellation.

Do we know Brutus’s parentage? Do we know for sure his mother wasn’t Caesar’s mistress back in 85 BC? Could “uncle” be a sly way of recognizing his bastard father?

Dad, go home. You’re drunk.

Caesar was only 15 when Brutus was born, and probably only 14 when Brutus was conceived, and there is no reason to think that he had even met Servilia (Brutus’ mother) at this stage. It was nearly twenty years, and two marriages, later that she was Caesar’s mistress.

Plus, if anyone seriously imagined that Brutus might have been Caesar’s son, much would have been made of this after the assassination. Patricide was the worst crime imaginable in classical Rome.