The father of a Florida cheerleader who died under suspicious circumstances aboard a Carnival cruise ship has been subpoenaed to testify in a bitter custody battle between his wife and her ex-husband.

Christopher Kepner is the father of 18-year-old Anna Kepner, who was found dead in her cabin around 11:15 a.m. on Nov. 7. She was on a family vacation with her father, stepmother, grandparents and some of her siblings.

The FBI is investigating her death — which her family told ABC News was ruled a homicide by mechanical asphyxiation.

TEEN FOUND DEAD ON CARNIVAL CRUISE SHIP DIED FROM MECHANICAL ASPHYXIATION, RULED HOMICIDE: REPORT

While the bureau hasn’t publicly identified anyone as a suspect, and no criminal charges have been filed, the feud in family court between Christopher’s wife, Shauntel Kepner, and her ex-husband, Thomas Hudson, has revealed that their 16-year-old son is being investigated by the FBI in connection with Anna’s death.

ANNA KEPNER DIES MYSTERIOUSLY DURING FAMILY VACATION ON CARNIVAL CRUISE SHIP: TIMELINE OF EVENTS

Read the subpoena:

Christopher Kepner has been ordered to testify during a Dec. 5 hearing in Brevard County, according to a subpoena filed by Hudson’s attorney, Scott Smith.

CHEERLEADER’S CRUISE SHIP DEATH HAS FAMILY POINTING FINGERS

After Anna’s death, Hudson asked the judge for custody of the daughter he shares with Shauntel, arguing in part that her parenting has directly put their 16-year-old son’s future “in jeopardy.”

“The Petitioner has not been allowed input into the children’s lives and his lack of involvement has negatively impacted the children,” Hudson wrote to the judge on Nov. 17.

CLICK HERE TO DOWNLOAD THE FOX NEWS APP

They also have an 18-year-old son who lives with Hudson. He went to live with his dad after an alleged “violent altercation” between himself, Shauntel and Christopher Kepner, according to court filings.

Christopher Kepner has not responded to Fox News Digital’s attempts to reach him.