Two members of Congress, including Arizona's Ruben Gallego, are sponsoring a bill to keep high-powered guns out of the hands of children.

The bill was introduced after the children of Charles Vacca gained national attention in their quest to ban assault weapons from being used by kids.

Vacca, a White Hills, Arizona gun range instructor at Bullets & Burgers, was shot and killed by a 9-year-old girl who lost control of an Uzi submachine gun while he was teaching her on Aug. 25, 2014.

His kids, who forgave the little girl in a letter, launched the initiative “We Have a Voice” calling upon others to let their state and federal legislators know that kids should not have access to high-powered weapons.

The campaign caught the attention of Rep. Gallego and U.S. Sen. Ed Markey of Massachusetts who introduced the new legislation in July.

If approved, the HEART (Help End Assault Rifle Tragedies) Act would prohibit anyone from even temporarily giving a machine gun or semi-automatic assault weapon to a child under the age of 16 including "for use in target shooting or on a firing or shooting range or for any other purpose."

The Vacca children have started a petition urging kids and parents to support the HEART Act as a "reasonable first step in ending gun tragedies involving our youth."

According to a spokesperson for the family, the legislation is now in committee and will be reviewed when Congress is back in session in early September.

The children also plan to file a wrongful death lawsuit against Bullets & Burgers and other related businesses, in order to "hold them and the industry accountable."

The lawsuit will coincide with the two-year anniversary of their father's death on Thursday, Aug. 25.

"They want to send a message to the gun entertainment industry that if it engages in the unsafe practice of giving children assault weapons and someone is hurt or killed, there will be consequences," a spokesperson for the family said.