Daniel Schuler, whose wife killed herself, their daughter and six others when she drove the wrong way on New York's Taconic State Parkway, is suing his brother-in-law -- whose three young daughters were among the victims.

Diane Schuler was driving a vehicle borrowed from her brother, Warren Hance, when she crashed head-on with another car on July 26, 2009. The crash took the life of Diane, her two-year old daughter, her three young nieces, and three men in the vehicle Schuler hit. 

Schuler's son, who was 5 years old at the time, was the only survivor in the car driven by his mother. 

Schuler denied that his wife was drunk and high at the time of the crash. In the immediate wake of the accident, he insisted that Diane never drank or used drugs, but later conceded that she occasionally smoked marijuana to help her get to sleep. He also admitted that she had consumed alcohol at earlier points in the weekend of the crash, but maintained that she had nothing to drink that day.

Toxicology reports found that Diane Schuler -- who was driving up to 70 mph for more than two miles before making impact -- had consumed marijuana and the equivalent of 10 shots of vodka before the crash.

Schuler insists that his wife must have been suffering from an illness that went undetected in the autopsy. He continues to insist that Diane was innocent of any wrongdoing, and this week filed two lawsuits claiming others were responsible.

On Monday, Daniel Schuler filed a lawsuit against the state of New York, claiming that the highway did not have proper signage and was poorly designed, which allowed his wife to drive in the wrong direction. Last week, he filed a lawsuit against his brother-in-law, alleging that Warren Hance is "vicariously liable" for the accident because he was the owner of the vehicle Diane was driving.

Warren and his wife Jackie lost their daughters Emma, 8, Alyson, 7, and Kate, 5 in the crash.

Shortly before the collision, Emma Hance called her father in distress. "Daddy, there is something wrong with Aunt Diane and she is having trouble seeing and she is talking funny, she is slurring," the 8-year old said.

An HBO documentary about the tragedy that premiered this week took its title -- "There is Something Wrong With Aunt Diane" -- from that phone call. The Hances declined to participate.

Jackie Hance is suing the estate of Diane Schuler for unspecified damages in connection with the death of her three daughters.