The car crash on the way to a slumber party left an 11-year-old girl dead, six other children hurt, a mother behind bars and New Yorkers with tougher penalties for drunken driving.

The driver who caused it all pleaded guilty to manslaughter, drunken driving and every other charge against her on Tuesday, days before the state law inspired by the case takes full effect.

Carmen Huertas, wiping her eyes with a tissue but answering a judge's questions with calm clarity, admitted she downed cognacs before getting behind the wheel of a station wagon full of children on Oct. 11.

Her relatives, victims' families and one of the injured girls packed the Manhattan courtroom. Some wore T-shirts and buttons memorializing Leandra Rosado, who died in the wreck and now has a state law named after her.

"Today, I was happy to see that Carmen Huertas has finally decided to be honest with herself that she was guilty of all charges — that she was guilty that night for drinking, being reckless and committing the acts she did," said Leandra's father, Lenny Rosado, who has become a seasoned activist against driving while intoxicated.

Huertas, who faces certain prison time at her Oct. 1 sentencing, crashed while driving her 11-year-old daughter and a half-dozen of her daughter's friends to a weekend sleepover at her Bronx home.

Huertas had taken the group to a family birthday party in Manhattan, where she got so drunk that other guests told her not to drive and her toddler son's father yanked the boy out of her car, prosecutors said.

She took off nonetheless, ignoring the children's pleas to slow down and taunting them to raise their hands if they thought they would crash, according to prosecutors.

When they did crash, Leandra died within minutes. The other children suffered a variety of injuries; Yiselle Rosario, who attended Tuesday's court session, walks with a cane after 11 surgeries.

Huertas, 32, was on suicide watch in jail for weeks after the crash, and "she remains remarkably remorseful for Leandra's death," her lawyer, Steven A. Rubin, said this week.

State Supreme Court Justice Charles Solomon has promised Huertas a sentence longer than the minimum range of one to three years in prison but shorter than the maximum range of five to 15 years. The ranges reflect the possibility of time off for good behavior.

Huertas remains behind bars until sentencing.

The state measure known as Leandra's Law — officially the Child Passenger Protection Act — passed a little more than a month after the wreck.

The law makes drunken driving a felony if a child 15 or younger is in the vehicle; the offense is generally a misdemeanor. Another provision, which takes effect Sunday, requires all convicted DWI offenders to outfit their cars with devices that prevent an engine from starting if the driver doesn't pass an alcohol breath test.

"These are powerful tools, in this new legislation, for prosecutors," Manhattan District Attorney Cyrus R. Vance Jr. said Tuesday.

Some lawmakers had pushed for such measures for years, but Leandra's death and her father's advocacy became catalysts for getting them passed. Lenny Rosado was at Gov. David Paterson's side when the law was signed.

"The tragic events that led to her death certainly justify the law," one of its main backers, Republican state Sen. Charles Fuschillo Jr., said Tuesday.

Rosado now hopes the rest of the nation will follow New York's example. He's set to meet with U.S. Department of Transportation Secretary Ray LaHood next week.

While the campaign for Leandra's Law has been emotionally wrenching, "I didn't want to let my little girl down," said Rosado, a hotel security manager. "She was my best friend."