Woman, 36, Dies in Pool of Friends : Tragedy: A neighbor in El Toro spotted the lifeless body. Meanwhile, a 5-year-old girl remained comatose after she and her 3-year-old sister nearly drowned Wednesday.

One day after two young girls nearly drowned in Fullerton, a 36-year-old woman was found dead Thursday at the bottom of a back-yard swimming pool in El Toro, authorities said.

Martha Munoz-Lemus was pronounced dead at the scene about 6:15 p.m. after attempts by paramedics to revive the Santa Ana woman failed, Orange County Sheriff’s Department Lt. Harold Schaffroth said.

A neighbor called 911 after spotting the victim on the bottom of the pool behind the two-story residence in the 25000 block of Owens Lake Circle in El Toro, Schaffroth said. The cause of death has not been determined; an autopsy will be performed.

Mark Burnett, the owner of the house, described Munoz-Lemus as a friend of the family who occasionally cared for his 2-year-old son.

It was not disclosed whether Burnett and his wife or their son were home at the time of the incident.

“She was a very nice woman. It doesn’t make sense,” Burnett said late Thursday. “She was a good swimmer. I don’t know how it happened.

“It’s very tragic,” he said. “She was a wonderful woman.” Burnett said he did not know how long the victim was in the water before she was discovered.

Nearby, Burnett’s wife was in tears.

Meanwhile, a 5-year-old girl who was found face down on the bottom of her grandparents’ swimming pool in Fullerton remained in critical condition Thursday at Childrens Hospital of Orange County in Orange.

Randi Newkirk and her 3-year-old sister, Robyn, were rescued from the pool about 1 p.m. Wednesday at 1831 N. Sunset Lane, where their grandmother, Lois Newkirk, was baby-sitting them. Paramedics and firefighters revived both girls at the scene before taking them to St. Jude Hospital and Rehabilitation Center in Fullerton.

Robyn was listed in good condition Thursday at St. Jude. A representative of Childrens Hospital, where Randi was transferred, said the child, whose chance for survival has been rated as slim, is breathing with the help of a respirator.

Authorities said Randi might have been under the water 10 to 15 minutes--more than enough time for brain damage to occur from a lack of oxygen.

Maureen Williams, director of public relations for CHOC, said Randi, who is in a coma, remains on life-support systems in the intensive care unit, with no change in her condition since the incident.

Sgt. Don L. Kimbro, a Fullerton detective, said Thursday that investigators have talked with Newkirk and have concluded that there is no evidence of wrongdoing or criminal negligence.

“Essentially, she was baby-sitting the children,” Kimbro said. “They got out of her sight for a while, and when she went to look for them she found one of the kids in the swimming pool.”

Newkirk, 59, spotted Robyn floating face down, pulled her to safety, made a 911 emergency call and told authorities that she could not find Randi.

A few minutes later, arriving firefighters saw the 5-year-old face down on the bottom of the deep end, which is eight feet deep. By the time they pulled her out, Randi was not breathing and her heart had stopped.

“This kind of situation can happen rather quickly,” Kimbro said. “We probably won’t proceed any farther. Our investigation is complete. The rest is just a tragic accident.”

Times staff writer Matt Lait contributed to this story.