A 14-year-old heir to one of America’s great fortunes is being sued for allegedly injuring a teen friend with a homemade explosive in Mount Pleasant.

Stephanie Pangle, the mother of the injured boy, recently filed a lawsuit against a 14-year-old heir to the Duke fortune and his mother, Daisha Inman, over the June incident.

The personal injury and defamation suit, filed in Charleston County courts, seeks more than $75,000 in damages, as well as funds to cover the wounded boy’s medical care and the potential loss of his future earning power.

The 14-year-old is the son of the late Walker Patterson Inman Jr., nephew of billionaire heiress Doris Duke. The teen and his twin sister are expected to be worth an estimated $500 million each by the time they turn 21.

Daisha Inman, Walker Inman’s fourth wife and the twins’ mother, gained custody of the children and settled on Sullivan’s Island after her ex-husband’s 2010 death from a methadone overdose.

Inman said she was unaware of the suit before being contacted by a reporter.

“She’s looking for a way to make money,” Inman said, noting that the suit was filed after a story in The Post and Courier detailed the children’s inheritance.

She said her children “are no longer allowed to be around” Pangle’s children because of the incident and resulting suit.

Charleston lawyer Samuel Allen, who represents Pangle, declined to comment, saying “the lawsuit speaks for itself.”

The June 1 incident occurred at a home on Fairmont Avenue where Inman’s son was visiting.

The injured boy’s father, Christopher Randles, told police that Inman’s son had been in the yard trying to light a homemade firework made from black powder in a plastic bottle. Randles said he told the boy not to light the device and made him pour the powder into another bottle, according to a police report.

Randles told officers that Inman’s son came running into the house a short time later and said another boy had thrown Randles’ son to the ground and smashed his face. Inman’s son later told Randles he had thrown the lit firework and the flame had burned the face of Randles’ son, police said.

Randles took his son to East Cooper Medical Center, where doctors determined that the boy had first-degree burns on his face and that his eyes had some burns, police said.

The injured boy’s parents told police they did not want to press criminal charges, according to a report.

According to the lawsuit, Daisha Inman later made threatening and slanderous statements against the injured boy’s parents.

Reach Glenn Smith at 937-5556 or Twitter.com/glennsmith5.