Photo:Sean Gardner/Getty

Sean Gardner/Getty
Jimmie Johnsonis speaking out for the first time after his mother-in-law killed her husband and grandson in asuspected triple murder-suicidelast month.
The NASCAR driver, 47, shared apost on social mediaFriday, in which he expressed his gratitude for the love and support he and his family have been shown following the tragedy that involved Jack and Terry Janway and 11-year-old Dalton.
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PEOPLE confirmed in June that Johnson’s mother-in-law Terry, 68, shot and killed her husband Jack, 69, and their grandson Dalton at the family’s Oklahoma home.
Terry and Jack — who are the parents ofJohnson’s wife Chandra— were found dead inside the residence along with Dalton, police previously said.
Muskogee police officer Lynn Hamlin told PEOPLE at the time that the department received a 911 from a woman they believe to have been Terry, “who stated that there was a disturbance and someone had a gun and then hung up” the phone.
When officers arrived shortly after 9 p.m. local time, they found an individual laying dead in a hallway of the home, and then heard another gunshot go off inside the house. The department said its officer then found two more bodies in another location in the house.
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“Please tell me this isn’t really happening please god someone,” Marianne Janway, Johnson’s sister-in-law, posted on Facebook around midnight after the incident.
“It was traumatizing to find out that a long-standing family who had made so many contributions to our community were involved in this type of incident. It was even more bone-chilling to find out there was a child involved,” Muskogee Mayor Marlon Colemantold local Fox 23 Newsat the time. “I knew Dr. Janway. Dr. Janway has worked on me, we’ve been acquaintances for a very, very long time since I’ve been in Muskogee. Just knowing that it was him and his family took a different toll on me.”
The district said counselors would be available for students, families and employees.
source: people.com