TAMPA, Fla. (WFLA) — The young brother of a baby who was found unresponsive at a Florida day care watched staff try to revive his sibling before he died, newly-released surveillance video shows.

NBC Miami reports 9-month-old Tayvon Tomlin died in an incident at Lincoln Marti Child Care on July 18. Three months later, his cause of death remains unknown, and his family is still seeking answers.

“I’m heavy with frustration,” Tayvon’s mother, Keiara Whorley told reporters at her attorney’s law office Monday. “I’m always going to be frustrated, hurt, crying, missing my baby, but right now, I have all the fight directed toward this case.”

Whorley and the child’s father, Devonte Tomlin, filed a lawsuit seeking compensation for mental pain and suffering and medical and funeral expenses.

“For me, that’s my first child,” said Devonte Tomlin. “I felt every pain in every nerve.”

Whorley and Tomlin’s lawyers released surveillance video Monday showing staff’s attempts to resuscitate their son as his 4-year-old brother watched. One is seen holding Tayvon face down and hitting his back as another tries to perform CPR.

“The video shows that this daycare did not provide its staff with adequate training. They clearly did not know how to perform appropriate CPR,” said attorney Stephen Cain.

Cain said she appeared to “be giving rescue breaths in her arms, with no compressions being done.”

“This is minutes in and they’re rubbing his back. That’s not effective and comprehensive CPR,” the attorney added.

The suit also alleges Lincoln Marti did not have adequate staff at the facility.

For children under the age of 1, there must be one day care worker for every four infants, the Florida Department of Children and Families says. The lawsuit claims there was only one person supervising eight infants.

“It’s a violation of the DCF standards, and it’s unacceptable, and unfortunately, it led to this outcome,” attorney Michael Levine said.

The DCF also requires day cares to provide parents with an incident report on the day it occurs, but the family said they still have nothing.

The medical examiner has yet to complete their report, according to the news station.

An attorney for the day care sent the following statement to WTVJ.

“It is my position, and that of my client, that it is not appropriate to discuss matters that are currently in litigation and most importantly that are still under investigation. My clients and I are sympathetic to the tragic loss experienced by this family, which as I’ve said, is currently under investigation.”