Bloomberg anti-gun ad marks 2nd anniversary of Ariz. shooting

This mother's passionate plea for gun control will air in living rooms around the country on the second anniversary of her daughter's death.

"My nine-year old daughter was murdered in the Tuscon shooting," says Roxanna Green. "I have one question for our political leaders: when will you find the courage to stand up to the gun lobby?"

"Whose child has to die next?"

Her daughter Christina was among the six killed and 13 wounded in the shooting at neighborhood event with then-Rep. Gabrielle Giffords on January 8, 2011. Giffords was among those wounded and who eventually resigned from Congress to focus on her recovery. Jared Lee Loughner pleaded guilty in August to 19 counts related to the shooting.

But Green remembers her daughter, the youngest victim of the shooting, and calls for action in a new television ad from New York Mayor Michael Bloomberg's Mayors Against Illegal Guns.

His group also enlisted celebrities to star in a recent video supporting the effort to "Demand a Plan" for action on gun control.

Green's daughter was a few years older than the 20 six- and seven-year-olds killed at Sandy Hook Elementary School in Newtown, Connecticut, at a shooting there December 14.

That shooting sparked a new wave of calls for gun control, including from leaders in Washington. President Barack Obama pledged "meaningful action" against gun violence and appointed Vice President Joe Biden to lead the effort.

Bloomberg applauded Obama's statement and urged him to take "immediate steps." On Monday, Bloomberg outlined his platform, including strengthening background check requirements and banning assault weapons. The assault weapons ban was enacted in 1994, but expired in 2004, and has not been renewed.

The influential National Rifle Association argued the Newtown shooting made the case for armed guards in schools as a line of defense.

The ad will run on cable in Washington, beginning Tuesday and will air through January 14 -- the one month anniversary of the Newtown shooting. Obama set the end of January as the deadline for Biden's group to report back.

It will run Tuesday only in Tuscon, Arizona, as well as other cities affected by gun violence: Binghamton, New York; Fargo, North Dakota; Roanoke, Virginia; and Waco, Texas; Denver and Milwaukee. In Tuscon, the group says the ad will run around 10:10 a.m. local time, to mark when the shooting occurred.

Giffords and her husband, astronaut Mark Kelly, also announced plans to mark the day. "Gabby and I are making an announcement tomorrow about our next project and the impact we hope to have in America," he posted on Twitter Monday evening, saying their effort would be announced in a newspaper op-ed piece.

Bloomberg's ad encourages people to sign an online petition on the group's website.

Christina, the nine-year-old, was remembered at her funeral as the only girl on her Little League team -- and one aspiring to the major leagues. She attended the Giffords event after her election to the middle school student council.

"To every mother, we can not wait," Green says in the ad. "We have to demand a plan."