A St. Mary’s County father was charged with involuntary manslaughter Thursday after he left his 17-month-old son in a car from about 8:50 a.m. to 3:30 p.m.

The child died Wednesday.

According to the criminal complaint, John MacDonald Junek dropped off his older son, a 4-year-old, at preschool Wednesday morning. He was then supposed to take the younger child to the Child Development Center on the base at Naval Air Station Patuxent River.

Instead, Junek parked his car and went to his office at the base. The temperature reached 85 degrees outside while the baby was in the locked car with the windows rolled up, an investigator said.

According to the criminal complaint, Junek told investigators that he drove to a meeting about 1 p.m. and drove back to his office about 2 p.m. without noticing that his son was still in the car.

At 3:20 p.m., his wife called to ask if he had their son’s car seat. Only then did he realize he might never have taken the child to the day-care center. He went back to the car, where he found the child unresponsive. He tried to perform CPR and called for help.

Junek, 40, of Leonardtown, Md., has been in custody since Wednesday. His attorney Robert Bonsib said that Junek and his wife have legally owned firearms in their home, which must be removed before Junek can be released. He said that Junek will likely return home Friday.

“It is very difficult when you have to deal not only with the death of a loved child and grandchild but also with the legal system,” Bonsib said. “We’re very pleased that he’s going to be released.”

Prosecutors said in a news release that the charge of involuntary manslaughter carries a maximum sentence of eight years in prison. Bonsib said he hoped the case would be resolved without a criminal penalty.

“There’s nothing in his background that would suggest that he’s anything other than a loving father,” Bonsib said. “It was a tragic accident.”

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