I just pulled these offline. Never used them myself, so make sure your mom asks lots of questions and looks up their reputability before pursuing them. Maybe others here have input on these groups:
http://www.aahahelpingpets.org/home/
"Through the AAHA Helping Pets Fund, veterinary care is possible for sick or injured pets even if they have been abandoned or if their owner is experiencing financial hardship."
Angels 4 Animals
www.Angels4Animals.org
"Our services range from financial aid to complete treatment
to those pets and pet owners in need."
Care Credit
www.carecredit.com
A credit card company for health care, including veterinary care.
"With a comprehensive range of plan options, for
treatment or procedure fees from $1 to over $25,000, we offer a plan
and a low monthly payment to fit comfortably into almost every
budget."
God's Creatures Ministry
http://www.all-creatures.org/gcm/help-cf.html
"This fund helps pay for veterinarian bills for those who need help."
Help-A-Pet
http://www.help-a-pet.org/home.html
"Our efforts focus on serving the elderly, the disabled, and the
working poor."
IMOM
http://www.imom.org
"We are dedicated to insure that no
companion animal has to be euthanized simply because their caretaker
is financially challenged."
The Pet Fund
http://thepetfund.com/
"The Pet Fund is a registered 501(c)3 nonprofit association that
provides financial assistance to owners of domestic animals who need
urgent veterinary care."
United Animal Nations
http://www.uan.org/lifeline/index.html
"The mission of LifeLine is to help homeless or recently rescued
animals suffering from life-threatening conditions that require
specific and immediate emergency veterinary care. We strive to serve
Good Samaritans and rescue groups who take in sick or injured
animals. In certain cases, LifeLine can also assist senior citizens
and low-income families pay for immediate emergency veterinary care."