I am not saying Julia is or is not responsible for the death of her mother, brother and 7 year-old son, but I found this comment that I read on another site interesting, insightful even.
Has it occurred to anyone that Julia and William planned the abduction of Julian to extort money from her sister and the plan went bad.

William may have have married Julia with the expectation that they would later get a big pay out from from Jennifer and two years later, when they are living in the same situation (wage garnishments, living with mom, no new stuff, no car…but your sister is a movie star)he convinced her of his master plan to help them get on…or vice versa.
She had to be resentful about driving a school bus and having no money when her sister is obviously not struggling. and how convenient is it that he knows her schedule and all of this went down while she was “at work”… but there was no school friday…she was the one to discover the bodies…but her brother is the person who normally picks her up…but he’s dead…how did she get home…
and why is she all at the house trying to get the mail after her whole family just got killed in there, she wasn’t paying her bills before why is she acting concerned about them now. If my baby and my mama were murdered IM SORRY BUT I WOULD NOT BE ABLE TO MOVE, COMPLETE A SENTENCE VERBALLY, LET ALONE, TYPE SOME SHIT ON MYSPACE.Very Very suspicious.
Something that’s unmentioned in this biased comment posted above is that neighbors reported that William vowed to “mess up” the Hudson family shortly before the murders when he got in an argument with them.
For now these murders look like a violent act of revenge not a master plan gone wrong. However, I heard Julia doesn’t seem sincere when she begged for her son’s return, I think it’s EFFING weird that she blogged about Julian a day after he was found dead, and bitch still has William as a top friend on MySpace. All that makes her look suspect.
Either Julia had an active role in the murders, or she has all kinds of sick, twisted issues.