A toddler’s visit to the dentist can be a nerve-wrecking experience for any child and parent. Sometimes, the unthinkable happens: A routine cavity-filling procedure last month at Austin Children’s Dentistry in Texas has left a young mother in agony after her 14-month-old daughter under anesthesia stopped breathing.

Daisy Lynn Torres was immediately rushed to North Austin Medical Center where she was pronounced dead five hours later. Her mom, Betty Squire, 26, doesn't understand how her baby could go for minor dental work and be dead hours later. Squire told Today she took Daisy for her first check-up when the little girl was six months. Two weeks ago after a subsequent visit, dentists told her to bring her daughter back to get two cavities filled.

"They told me that they were going to put her under and the procedure was going to take 40 to 45 minutes and I should go to the waiting room," said Squire.

Typically, in a filling appointment, the dentist will start with a quick inspection to confirm the job that can be done. Then a local anesthetic — which blocks pain — is used if necessary, although most fillings on baby teeth can be completed without one, according to the Baby Center. In addition, a topical anesthetic gel may be used to lessen the feeling in the gum before administering the anesthetic.

The decay is removed with a drill or hand instruments. The dental nurse or dentist will suck away the water and debris from the drilling. The cavity is then filled with amalgam (silver filling) or composite (tooth-colored filling). After a quick bite down and a rinse the procedure is done.

However, Daisy Lynn did not have such success. Shortly after beginning, the dentist came out and said more extensive work needed to be done, according to Squire. Ten minutes later, the dentist admitted to Squire something went wrong and the baby started having trouble breathing and went into cardiac arrest.

“We did CPR and she's fine now. We called EMS to monitor her because that's standard,” Squire recalled being told.

"I put my child's life in their hands and I am not able to bring her home with me,” she said.

Sarah Marshall, a spokeswoman for Austin Children's Dentistry told NBC affiliate KXAN, "I don't know the details of this specific situation. The staff here is waiting to hear additional details of what exactly the medical examiner's office releases."

Marshall did confirm that a dentist and an anesthesiologist were in the room. The Texas State Board of Dental Examiners is currently investigating the death after hearing about it through media reports, according to Lara Anton, board spokeswoman. Generally, a dentist has 72 hours to report a death to the board. Information from dental records, the medical examiner’s office, the dental office, the dentist and anyone else who was there is gathered in the process. The company’s website shows none of the six dentists listed as working for Austin Children’s Dentistry have been disciplined in Texas for any action before.

Squire and the rest of Daisy Lynn's family members are waiting to hear what could have led to the death. The investigation could find that the dentist followed protocol, or is guilty of misconduct, and revoke his or her license.

Meanwhile, family friend Rachel Robinson set up a page on You Caring to raise funds for Daisy’s funeral.

Robinson wrote: “Daisy Lynn Torres went in this morning for a routine cavity filling and under the advice of the dentist was put under anesthesia, when the unthinkable happened. Daisy quit breathing and was rushed by ambulance to a local hospital where despite efforts by the hospital staff, she passed away this morning.”

A GoFundMe page has been set up to raise money for the Torres’ family funeral expenses.