HARRISBURG –  The wife of Lt. Gov. Mike Stack has begun seeking in-patient treatment for a mental health problem, amid an inquiry ordered by Gov. Wolf into whether the couple verbally abused and mistreated employees who worked for them.

Tonya Stack, 47, checked into a treatment facility to receive assistance in coping with a mental health problem, Marty Marks, Stack's onetime campaign manager, said late Thursday. Marks would not describe the health problem, the treatment she is receiving, or where she is getting help.

Marks called the problem “a deeply personal matter” and said only that Stack had taken steps to protect his family's “health and well-being.”  The news was first reported by LNP Media Group.

In a statement, Matt Franchak, Stack's chief of staff said:

"The Lieutenant Governor will not be discussing the particulars of his wife's treatment and has nothing further to add at this point other than that he loves his wife, admires her courage and believes they will emerge from this experience as a more compassionate and loving family."

Franchak added: "As a public servant, it is the Lieutenant Governor's duty to answer legitimate questions relating to his interactions with state employees. As a husband, however, he does not believe it is fair to attack his wife for the manifestations of her illness. It is unfortunate that some have repeatedly done so rather than attempt to understand what was happening or offer to help."

The news caps a politically bruising few weeks for Stack, the longtime Northeast Philadelphia state senator and his wife. In April, news surfaced that he and his wife were under investigation – at Gov. Wolf's prompting – by the state Inspector General's Office for alleged mistreatment of the state police troopers who guard them and the state employees who work at the lieutenant governor's official residence.

Stack held a news conference in his Capitol office during which he apologized for himself and his wife, acknowledging that when stressed and angry he had lapses into a "Stack moment." But he refused to describe the behavior for which he was apologizing or discuss his treatment of employees in any detail.

The controversy has laid bare the souring relationship between Wolf and Stack, both Democrats up for reelection next year. Although they ran on the same ticket in 2014, Wolf did not choose Stack as his running mate, and the two men have not been close.

Wolf told reporters last month that he warned Stack numerous times that there had been complaints about his behavior.

Also, in an extraordinary move, he stripped the Stacks of the state police detail that protected them and drove them in a state-issued SUV equipped with police radio and flashing lights. He also scaled back staffing at Stack's taxpayer-funded house outside Harrisburg, saying employees would be dispatched there only at arranged times and only under supervision.

The Stacks have been married since 2001. 

7:45 am: Story has been updated to include a statement from Matt Franchak, Stack's chief of staff.