The girls, both 9 and members of a Lake Stevens cheerleading squad, had done a great job at a game that afternoon.
The special treat turned into a nightmare for the Riojas family.
Riojas' daughter, a third-grader, became violently ill after she came into contact with E. coli allegedly at the restaurant on Oct. 11, her mother said.
Snohomish Health District officials said Wednesday four additional cases were connected to the Lake Stevens restaurant. As of Wednesday afternoon, 17 out of 19 E. coli cases in Snohomish County were traced to the Mexican restaurant.
The Riojas family filed a lawsuit Wednesday morning against Ixtapa, blaming the restaurant for their daughter's severe attack of E. coli. They want the restaurant owner to pay for their daughter's medical bills.
"I don't think it was intentional. We've gone to the restaurant a number of times. We love Ixtapa. It's a local family restaurant. The owner has been very kind," Alison Riojas said. "I know they'd never do this to a 9-year-old girl on purpose, but it happened to her at their restaurant."
Riojas' daughter was hospitalized and lost at least 6 pounds from her 64-pound frame. She pleaded for help to ease the pain caused by the bacteria.
"She was begging for relief. She was praying," Alison Riojas said Wednesday. "She was in so much pain and there was nothing I could do."
Public health officials continued Wednesday to interview restaurant patrons about what they had eaten in an attempt to pinpoint the source of the bacteria.
Riojas' daughter and her friend ate chips, salsa, guacamole, a chicken enchilada, rice and beans. Alison Riojas ate the same meal, except she didn't have guacamole.
Riojas and her husband didn't get sick, and neither did their other daughter, 6, who chose not to eat that day. Their older daughter's friend did get sick, Riojas said.
"It was like Russian roulette with food. I wish I would have been given the food instead of her," Alison Riojas said.
It isn't clear if health officials will be able to find the original source of the contamination, said Rick Zahalka, food program manager for Snohomish Health District.
"We sent in one sample of a cheese, but after further investigation it was ruled out," he said. "The trouble is the time lag. There is an incubation period; if a person gets sick or develops symptoms it's several days after they've eaten the contaminated food, then another several days for the lab results from the doctor. By then the food is gone."
Riojas' daughter complained of some stomach pain but didn't have a fever. She was sent home from school Oct. 14 and became increasing ill with diarrhea.
Riojas took her daughter to the emergency room at Providence Everett Medical Center twice on Oct. 16. The girl was treated for dehydration and pain and released both times. Her symptoms worsened and the next morning she was rushed to the emergency room at Children's Hospital in Seattle, where she began to vomit blood, according to court documents.
"She was crawling down the hall to get to the bathroom," Riojas said.
The girl tested positive for the same strain of E. coli associated with the outbreak at Ixtapa, according to the lawsuit.
The Riojas' attorney is representing four other families affected by the E. coli outbreak. More lawsuits are expected to be filed, said attorney Drew Falkenstein.
Falkenstein is with Marler Clark, a Seattle law firm that has represented thousands of people in food poisoning cases, including the E. coli outbreak connected to Jack in the Box in 1993.
"This was a serious outbreak. Here in Snohomish County we don't have very many foodborne outbreaks a year -- thank goodness -- and I don't have another big E. coli outbreak to compare this to," Zahalka said. "We will be monitoring Ixtapa. We'll be working with the restaurant to make sure that all food safety requirements will be complied with."
The restaurant's owner is taking these illnesses very seriously, Bellevue attorney Stephen Pidgeon said.
"Obviously we have our concern about what the source may be," he said. "Ixtapa is a very sanitary restaurant and very professionally ran restaurant."
The health of the restaurant's patrons are the owner's top priority, Pidgeon said.
The health district Wednesday approved reopening of the restaurant after extensive cleaning. Ixtapa's owner expects to reopen as soon as the restaurant receives a shipment of new food stocks, Zahalka said. Restaurant workers tossed out any food in unsealed containers, sanitized the kitchen, work spaces and utensils and replaced cutting boards. The employees were retrained on food safety, Zahalka said.
Doctors say Riojas' daughter should make a full recovery but for the next two weeks her parents must watch for signs of a syndrome associated with E. coli contamination that can lead to more serious problems.
The girl was only able to drink water and eat ice chips until Tuesday, when she was finally able to nibble on a bagel and an English muffin.
She has little energy, her mother said. She naps for hours, and playing a board game wears her out, Riojas said.
She hopes the outbreak will motivate legislators to make tougher laws to protect restaurant patrons.
"We live in a country where you shouldn't feel scared to take your children out to a restaurant," Riojas said.