Galvin's mother battled breast cancer and just six months after she passed, Galvin learned of her diagnoses.
49ers CEO Jed York tweeted out the news last night.
She was first diagnosed in 2011 after discovering a lump while breastfeeding her daughter.
Galvin was part of the Gold Rush squad from 2000 until 2005 and remained a mainstay on the sidelines during games helping to coordinate field events. Her public battle against breast cancer did a tremendous amount to raise awareness through her own fundraisers and was featured during the NFL's breast cancer awareness campaign which runs every October.
Galvin, who was 34, leaves behind husband Patrick Dobson and two young children, Stella and Brady. She was a Stockton resident and ran Dance Xtreme, a local dance studio.
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