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WATCH: Ad featuring mom of young Tucson shooting victim debuts as part of mayor’s push for tougher gun laws

A powerful ad featuring the mother of a murdered nine-year-old gun victim asking “whose child has to die next?” began airing today as part of Mayor Bloomberg’s push for tougher national gun laws.

The ad is being shown in six cities where there have been mass shootings, as well as Washington DC.

In Tucson, Ariz., it will be seen at 10:10 a.m. — the exact time two years ago when a crazed gunman killed six people and severely wounded former Rep. Gabrielle Giffords.

The “Demand a plan” ad begins with Roxanna Green, who lost her daughter Christina-Taylor in the mayhem, speaking about the horror at Sandy Hook, where 20 young kids were gunned down.

“I know how much it hurts,” Green says.

“My nine-year-old daughter was murdered in the Tucson shooting. I have one question for our political leaders. Who will find the courage to stand up to the gun lobby? Whose child has to die next?”

Bloomberg’s Mayor’s Coalition Against Illegal Guns is paying for the ads. There was no immediate estimate of the cost.

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