The entire family was attending the celebration on Antoine near West Little York when someone started shooting outside the party.
Witnesses say the gunmen fired more than 10 shots, and one of the bullets went through the building and hit the woman while her family members watched.
"The bullet is in the door over there. You see the bullet went though the glass and it her. She's a nice, sweet mother," witness Joe Torres said.
The woman was shot in the abdomen, but is expected to survive her injuries.
The shooter remains on the run.
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