Even though he's dead, a woman in the U.S. is suing Ahmed Said Khadr for $10 million US in damages.

The woman is a widow of a U.S. soldier who was killed in a battle with al Qaeda militants in Afghanistan.

The lawsuit alleges that one of Khadr's sons, Omar, threw a grenade at the woman's husband, Sgt. 1st Class Christopher J. Speer. The grenade attack sent shards of metal into Speer's head, killing him.

"They fought in a physical firefight, but there are other ways to do that and one of the ways is to hit al Qaeda in the pocketbook and that's what we're trying to do with this suit," said Donald Winder, lawyer for the plaintiffs.

It's alleged that Khadr was the patriarch of a family that took part in terrorist activities after learning radical Islamic values from their father.

A draft version of the lawsuit says, "Khadr had a duty as a parent to exercise reasonable care to control" his son Omar. Another of Khadr's sons, Abdurahman, recently admitted that his father repeatedly urged him to become a suicide bomber. He also called his own clan an "al Qaeda family."

Ahmed Said Khadr was an Egyptian-born Canadian. As a man who considered Osama bin Laden one of his closest friends, Khadr was on the radar of international intelligence agencies for a long time. Last year, he was killed in a gunfight with Pakistani authorities.

His youngest son, Abdul Karim, now 14, was partially paralyzed in the battle that killed his father. He's has since returned to Canada with his mother to seek medical care.

However, Dennis Ebney, the Khadr's lawyer, said Omar never belonged to al Qaeda, nor did he toss the grenade.

"Until evidence comes foreward, Omar Khadr is entitled to the presumption of innocence," he said.

Omar, now 17, is in U.S. custody at Guantanamo Bay in Cuba. His lawyers recently filed a petition unrelated to the Speer's case. It claims that Omar's detention is unlawful because the teen has "no military or terrorist training, nor has he at any time voluntarily joined any terrorist force."

The petition denies that Omar was ever a member of al Qaeda. It also says that it wasn't Omar who killed Speer.

Terrorists and their pocketbooks

Speer's wife was left with two young children after her husband died. She believes they're entitled to a share of Khadr's money.

It's unclear how much Khadr's estate is actually worth. His assets were frozen in an effort to dismantle al Qaeda. "It could be $10," the woman's lawyer said. "It could be $10,000. It could be $110,000."

Even if the woman wins the lawsuit, it's not certain she'll have an easy time accessing the funds, since Khadr was Canadian.

"If some day we get a judgment and we show up in Canada, what your courts are going to say about the enforcement of the American judgment, I don't know," Winder said. "But someday, hopefully we'll have that judgment and we'll come knocking."

Also taking part in the lawsuit is a former U.S. army reservist, Sgt. 1st Class Layne Morris. He permanently lost vision in his right eye in the same fight in which Speer died. He says his motivation in joining the lawsuit is to bankrupt terrorists.

"It's something that has to be done," he said. "I don't think as a Western civilization we can allow people to just flow in and out of our society and declare war on us."

Morris called the Khadrs "Canadians of convenience" who get all the benefits of living in a Western society, but conspire to destroy it at the same time.

There is a precedent for the case. A judge in Rhode Island recently ordered the Palestinian group Hamas to pay $116 million to the family of a couple gunned down in Israel.

But there could be a number of legal hurdles for the case as well. The legal definition of terrorism in the United States Code does not include "acts of war." But Winder is hoping to prove that Omar was aligned with al Qaeda, and his actions could be characterized as terrorism.