William Balfour: Suspect in Jennifer Hudson Family Murders

William Balfour, a suspect in the Jennifer Hudson family murders, is in custody. Her mother and brother are dead, and her seven-year-old nephew is missing.

Balfour was once married to J-Hud's sister Julia - the mother of Julian, the boy who is unaccounted for. An AMBER Alert was issued for Julian as of yesterday.

In a cryptic statement, a Chicago PD spokeswoman has said that investigators are talking to "a number of people in custody" but didn't explain further.

At least one of the victims - Jennifer's mom Darnell Donerson and brother Jason Hudson - had defensive wounds, which may suggest domestic violence.

William Balfour was recently paroled after serving seven years in jail.

Here's the interesting thing - according to TMZ, neighbors in the Chicago area who know the family well say a few weeks ago a family member tried stealing a car, which triggered an argument in which the would-be thief vowed revenge.

No one was named specifically in the incident, but William Balfour, who is currently on parole and lists Donerson's address as his, spent nearly seven years in prison for attempted murder, vehicular hijacking and possession of a stolen vehicle.

Julia's MySpace page recently showed a picture of Jason with a caption that reads, "Jason picking up my ass from work, cause bitch ass William sold my car."

Follow the jump for more on the car theory that police are investigating in connection with the killings, and William Balfour's MySpace page ...

Several other neighbors said Julia complained to them that William Balfour sold one of their cars without permission. One neighbor told TMZ that the dispute got so heated William actually threatened to "kill Julia's family."

That's all circumstantial evidence, but Balfour is clearly an unsavory character (unless of course he's reading this, in which case we're obviously kidding).

Anyway, calling himself "FLEX A MILLION" on MySpace, Balfour says:

I AM A 26 YEAR OLD, I RESIDE ON THE SOUTH SIDE OF CHICAGO, I HAVE A WIFE HER NAME IS JULIA, AND I ALSO HAVE A 6 YR OLD STEPSON, I DON'T TOLERATE BULLSHIT, SO DON'T COME TO ME WITH IT, I LIKE TO LIVE LIFE AND EXPERIENCE EVERYTHING THATS WHY I'M HERE SEEING WHAT IT'S ABOUT, I MIGHT AS WELL LET YOU ALL KNOW THAT JENNIFER HUDSON IS MY WIFE'S SISTER I'M PROUD OF HER AND WISH HER NOTHING BUT THE BEST IN WHAT SHE DO BUT DON'T HIT ME UP ASKING BOUT HER, OTHER THAN THAT IT'S ON!

William also lists himself as a "proud parent," Julian is still missing.

More on this story as it develops ...