A second child has died after a routine appointment at an Arizona dentist office that is the target of a wrongful death suit involving another child who died after an appointment there.

KXNV reports that two-year-old Zion Jay Gastelum died after visiting a dentist in Yuma last month. The toddler’s family told the news station that Zion went to Kool Smiles Dentist on December 16 for a filling and a crown, and stopped breathing during the procedure.

He reportedly died at a hospital four days later, on December 20.

The precise circumstances of Zion’s death are not yet known, and KTLA reports that the Maricopa County Medical Examiner’s Office is investigating to determine the cause of death.

Less than a year before Zion died, Liseth Lares developed a high fever the day after her mother Francisca Lares brought her in for a routine dental appointment at Kool Smiles, reportedly to treat cavities and an abscess.

“The mom called back reporting signs of fever from her daughter, the dentist looked at the child, did in our view a relatively cursory exam, sent her home, told the mom essentially there is nothing to worry about she’ll be fine,” Lares’s attorney Marco Mercaldo told KRON.

“Unfortunately the infection spread and she died of infection,” Mercaldo said.

Lares has filed a wrongful death complaint against Kool Smiles.

“They took half of my heart,” Lares told the news station.

“They took something from me that will never come back.”

A trial date in regards to Liseth’s death is reportedly scheduled for 2016.

The Yuri Fire Department confirmed to KTLA that they were involved in “emergency medical response” at Kool Smiles in December, but authorities have said very little about the toddler boy’s death so far.

A spokesperson for Kool Smiles emailed the following statement to KTLA:

“The Kool Smiles family expresses our sincere, heartfelt sympathy to the family of Zion Gastelum. Our hearts are breaking for Zion’s family at this very sad time. Since Kool Smiles’ founding nearly twenty years ago, we have safely and compassionately provided needed dental care through more than 19 million patient visits. Our dedicated dentists, anesthesiologists and the rest of our Kool Smiles family join the community to mourn this tragic loss.”

Zion Gastelum’s relatives have launched a GoFundMe campaign to help raise funeral expenses.

“He was just the apple of everybody’s eye and the light in their hearts,” Zion’s grandmother, Norma Yarrito told the news station.

“He was just so loving that everybody loved him.”

It appears to be business as usual at Kool Smiles in Yuma. CrimeOnline called the office on Monday and a receptionist said the dentist’s office is taking new patients.

Feature image: KTLA screenshot/Zion Gastelum