An Air Force couple who reportedly had financial issues and concerns about child care costs is being investigated for the death of their infant son in 2016 and for serious injuries to a second young child, a daughter, in 2017, according to court records.

Technical Sgt. Caleb W. Humphrey, with the 792nd Intelligence Support Squadron, and his wife, Staff Sgt. Natasha C. Beyer, part of the Joint Intelligence Center, unsuccessfully fought the release of financial records sought by the Pentagon’s Inspector General.

The Kapolei couple is being investigated for involuntary manslaughter, aggravated assault, intentionally inflicted grievous harm and child endangerment, according to U.S. District Court filings.

“I don’t have anything to say to you, sir,” an individual who answered Humphrey’s cellphone number said Wednesday.

Joint Base Pearl Harbor-­Hickam referred questions to the Air Force Office of Special Investigations in Quantico, Va., which couldn’t be immediately reached for comment.

On July 18, 2017, Child Welfare Services notified the Air Force that Humphrey and Beyer’s daughter, Avaline Noel Beyer, had been admitted to Tripler Army Medical Center for seizures.

A medical exam revealed the girl, who was born that year, suffered from “numerous” brain bleeds, a skull fracture, bruising on the top of her head and face, and four rib fractures, court filings said.

Humphrey said he had tripped while holding the child, and while grappling with her accidentally slammed her face against his shoulder, according to a declaration filed by Roberto Flores-Rendon, a special agent with the Air Force Office of Special Investigations at Joint Base Pearl Harbor-Hickam.

But Lt. Col. Shelly Martin, a child abuse pediatrician at Brooke Army Medical Center in Texas, said the injuries were consistent with “non- accidental trauma,” with the rib fractures possible from squeezing, while the others could have occurred from a “single shaking/blunt force trauma type event,” Flores-Rendon noted.

Dr. Kayal Natarajan, a Honolulu-based medical consultant, subsequently reported that the girl’s injuries could not be explained by Humphrey’s description of what happened, according to Flores-Rendon.

The investigation of the girl’s injuries “revealed additional possible issues” relating to the 2016 death of the couple’s son, Grayson Caleb Beyer, who was born that same year and treated at Tripler, Flores-Rendon said.

The investigator’s declaration said the manner of death was ruled “natural” and consistent with suspected herpes simplex virus infection.

A postmortem scan revealed multiple healing rib fractures, but law enforcement was not deemed necessary at the time, Flores-Rendon reported.

Martin, the child abuse pediatrician, later found no indication of an active herpes infection and concluded that “non-accidental trauma should have been more thoroughly considered,” the declaration states.

Dr. Christopher Happy, Honolulu’s chief medical examiner, reviewed the case and in December determined the cause of death to be blunt force injuries to the head and ruled it a homicide.

According to the declaration, an Air Force civilian who knew the couple said Beyer talked about problems with debt prior to the boy’s birth, and “they talked in general about the costs of a child.”

“They had expensive tastes and could not really afford their lifestyle,” the statement said. An insurance payout of $10,006 was made after the boy’s death, Flores-Rendon said.

The couple’s military lawyers, in trying to stop the financial records search, said the couple did not live in an overpriced home, with their combined $4,275 a month housing allowance covering their $2,916 mortgage.

“Just because two new working parents talked about possible expenses related to their child’s care does not warrant that they want to hurt their children in order to get some insurance money,” the lawyers said.