"Life is such a funny thing. You think you have it all together and everything seems to be going along just fine, when, bang, somebody comes and knocks it all out of whack," Corey wrote. "I never would have guessed when I woke up this morning to singing birds and a clear blue sky that by afternoon my college career would be over and my new aspiration would be to collect garbage in the city. Yes, life -- the devilish tricks it can play on you."
Ms. Corey lived in a cozy Wyman Park rowhouse with an inviting porch swing, hydrangeas and roses that bloomed bountifully in the summer, and a changing lineup of pets. That included an excitable part-Papillon named Lily, whom Ms. Corey brought to work when she spent the night in the newsroom during the February 2010 "snowmageddon." Her last tweet this winter was simply a picture of a therapy dog brought in to cheer her during a hospitalization.
Her love of rescue dogs in particular led to a stint as The Sun's pet blogger beginning in February 2009.
To introduce herself on the blog, she introduced her dog, sweet Gracie, who had recently died. Gracie's human remembered picking her up 16 years previously at the Maryland SPCA, where the card on her cage, "Found in Hampden, terrier mix," hardly described how the mutt would weave itself into Ms. Corey's life.
"She will make even your best days better," Ms. Corey imagined the card saying. "She will comfort you through the worst of what comes. You'll be giving her a bath on a Saturday morning when the phone will ring, and the voice on the other end will tell you that your father is no longer alive.
"When you return the engagement ring, she will sit with you on the front porch as the news sinks in. And when the lump you felt turns out to be malignant, you'll leave work and go home because the thing you most want to do is hug your dog and take her for a walk."
It was a rare public revelation from Ms. Corey, but reflected her soft-hearted yet clear-eyed outlook.
When her companion, Paul Mattix, battled a recurrence of lymphoma, Ms. Corey studied research papers to find the most knowledgeable specialists and the most promising treatments, all the while caring for him until his death in 2005. Similarly, she and her friends rallied around Alice Steinbach, the Pulitzer Prize-winning former Sun writer, as she struggled through the cancer that would claim her life last year.
Friends recall how she helped Ms. Steinbach move to Seattle during her final year, only to see her return to Roland Park Place near Ms. Corey's home. When Ms. Corey couldn't fit Ms. Steinbach's huge wooden dining table in her car to drive it over to her friend's apartment, she started rolling it down the street — by herself until a neighbor jumped in to help.
"Mary, that is you," her friend Ms. Banisky recalled telling her. "Indomitable and a little crazy."
That Ms. Corey herself would be diagnosed with breast cancer in 2008 brought heartbreak to her family and friends. In typical fashion, though, she dove into the research, and maintained a determined and optimistic front through multiple surgeries and treatments.
"She had a kind of very brave curiosity about her disease," said Dr. John Fetting of Johns Hopkins, Ms. Corey's oncologist. "She was fearless in seeking out information, advice and ways to treat it.
"And she was such a dear and friendly person about it all. You always wanted to help Mary. Everyone on our team here was: 'What can we do to help?' She had this quality, that people wanted to be on her team."
Dr. Fetting added, "It was totally my privilege to be on her team. She was one of our good human beings and we need people like that."
In an introduction to a 2010 Sun special section on breast cancer awareness, Ms. Corey wrote that her approach to life had changed.
"After five months of chemotherapy and five surgeries, I'm now learning what it's like to live in the hereafter," she wrote, "and how happiness becomes part decision, part act of defiance."
She repeatedly returned to the newsroom, stubble of hair in the process of growing back or puffy from medications, but in bright spirits that allayed her co-workers' concerns. Back in her office overlooking Calvert Street, she seemed unstoppable, until the final bout.
But she was well aware of the severity of her particular strain of breast cancer, and the real possibility of a foreshortened life.