Walsh was 37 when she was diagnosed in 2014 with Stage 4 triple-negative breast cancer, a very aggressive form.
"When you're told you've got three years to live and you're only in your 30s and you've got little kids, there were some mental things I had to go through before I said, 'Nope. That's not what I'm going to do,'" Walsh said.
Walsh found a new oncologist at Seattle's Swedish Hospital who put her on an aggressive treatment regimen that included chemotherapy, a double mastectomy, radiation, more chemo and, most recently, two clinical trials.
Her cancer is now in remission, though Walsh recognizes that her battle isn't over. And the disease isn't the first obstacle she's had to overcome. In 2010, with two small children and a baby on the way, Walsh's husband, Brian, a Federal Way police officer, died suddenly of a heart attack.
Once she was diagnosed, Walsh was forced to step away from her 18-year career in the Air Force Reserves. Now, she's using her energy from those two challenges to work as an advocate for the rights of surviving spouses to receive death benefits, even if they remarry, as well as posting on social media about her struggle with cancer and the need for early detection.
"Every once in a while, I'll have an old friend or acquaintance say, 'I went and got checked because of your post,'" Walsh said. "And I think that's really cool if it can save someone's life just by giving out information."
Now, Walsh will look to further raise awareness by participating in the Honorary Bat Girl program that Major League Baseball introduced in 2009 as part of its annual "Going to Bat Against Breast Cancer" initiative.
Greg Johns has covered the Mariners since 1997, and for MLB.com since 2011. Follow him on Twitter @GregJohnsMLB. This story was not subject to the approval of Major League Baseball or its clubs.