Charles and Adrienne Snelling. (Cedar Crest College)

Snelling took his own life and that of his ailing wife Thursday at their home in Fogelsville, Pa., authorities said. They were both 81.

Adrienne Snelling had suffered for six years with Alzheimer’s disease and her husband was her primary caregiver. He often brought her along, paying travel expenses for her caregivers, when he came to the D.C. area for meetings.

Paul Hoffman, a coroner in Leigh County, Pa., said Monday his office was awaiting the results of additional testing and toxicology reports. Those results could take a couple of weeks to receive, he said. The investigation is pending.

The Snellings were married for 61 years and had five children and 11 grandchildren.

On the airports authority board, Snelling helped oversee the management of Dulles and Reagan airports and the $6 billion construction of Metro’s new Silver Line.

He was also known for presiding over the debate about whether to build a Metro station above- or below- ground at Dulles Airport. Ultimately, the board agreed to build it aboveground.

On Snelling’s watch, the board also wrestled with funding issues related to the second phase of the Silver Line, which would extend service to Dulles Airport and Loudoun County. It also argued with Virginia officials about a project labor agreement for the Silver Line and adding more members to the board from Virginia.

Three years ago, Adrienne Snelling wrote letters to her children and grandchildren explaining how she and her husband decided to cope with her illness.

In the letter, she wrote, “All of our lives, Dad and I have talked over our end of life beliefs. We are both in agreement that neither one of us wants to live after all reasonable hope for a good life is over. . . .We have had such a great life together and with all of you.”

On March 29, just a week after their 61st wedding anniversary, Charles took his own life and his wife’s. Authorities said Charles shot himself.

One of the couple’s children, Marjorie Snelling, 56, of Philadelphia, said Friday that she knew her parents had talked about a plan to end their lives but that she and her siblings were stunned that it actually happened. There had not been “any specific signs.”

Still, she said, her family believes the pair “were deliberate and thoughtful.”

“They had a plan, and they were going to execute that plan without people knowing,” Marjorie said. “They’ve seen their peers and friends languish. . . . They had really been thinking about this for some time and keeping it a secret.”

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