Her husband, Fort Worth police Officer Hank Nava, was fatally shot while investigating an identity theft ring in November 2005 -- making Teresa a widow and leaving their two children fatherless.
His death has spurred Mrs. Nava to try to help families of other officers killed in the line of duty.
Mrs. Nava, along with five of Officer Nava's closest friends, has started a foundation called H.A.N.K. -- Helping Another Next of Kin.
The nonprofit organization will hold its first fundraiser on March 31 at River Ranch in the Fort Worth Stockyards. Participants can run the 4-mile race or the mile "fun run" in Officer Nava's memory.
Mrs. Nava said she hopes the fundraiser will support local police officers and their families in several ways.
"The kids and I got such an outpouring of support when Hank died. I just wanted to give back," Mrs. Nava said. "It's my mission. Not enough is done when an officer is killed in the line of duty."
Her husband, she said, died without a will.
Mrs. Nava wants young recruits to learn from her husband and understand the importance of "getting your affairs in order."
In addition to preparing wills, the foundation hopes to provide financial assistance for families, money for police equipment and scholarships for the children of fallen officers.
"What she is doing is wonderful," said Lee Jackson, president of the Fort Worth Police Officers Association. "We have been so fortunate in Fort Worth not to have more officers killed in the line of duty. Teresa Nava is trying to put the community and fellow officers in front of herself, and we are grateful for that. She is an inspiration."
Mrs. Nava said she started H.A.N.K. to keep her husband's memory alive.
She put her own grief aside when another police officer, Dwayne Freeto, 34, died in December while assisting a stranded motorist. His death came a little more than a year after Officer Nava lost his life.
Mrs. Nava, recovering from her own loss, attended the funeral.
"I felt like I was watching what I looked like a year ago, but I wouldn't have missed it," Mrs. Nava said. "It brought back pain, but I wanted to be there for them. Even with Hank being gone, I'll support law enforcement forever. It's in my bones. And, I'll always be grateful for what they've done for me."
The H.A.N.K. (Helping Another Next of Kin) Foundation was formed by Teresa Nava and five of Officer Hank Nava's closest friends.
A 4-mile run on March 31 at River Ranch in the in the Fort Worth Stockyards will help raise funds to provide:
-- Wills, completed at no cost, to graduating police cadets
-- An annual scholarship to a child of a police officer
-- Money to buy equipment for specialized units in the Police Department
-- A donation to the family of an officer killed in the line of duty