Before a Newport Beach couple were found slain in their home last week, they became concerned about increasingly erratic behavior by the son who is now charged in their deaths, and they hired someone to investigate him, according to the private investigator on the case.

Michael Youssef of the firm Blue Systems International said Richard and Kim Nicholson first reached out to him in early February, weeks before they were found dead along with their housekeeper, Maria Morse, in their home in the gated community of Bonita Canyon on Feb. 13.

“They hired me because they wanted to find their son and wanted me to surveil him and build a case for conservatorship,” Youssef said. “They felt that he’s not acting normal.”

Their son, Camden Nicholson, 27, is charged with three counts of murder. He is expected to appear in court for arraignment March 8. He is being held without bail.

Camden Nicholson had stormed out of the home Dec. 13 after a heated confrontation and stole his mother’s car and vanished, Youssef said he was told.

“They feared that he might have committed suicide or is in the hospital somewhere,” Youssef said.

The Nicholsons told the investigator that Camden had been a normal, happy child, but after going away on a Mormon mission for nine months when he was 19, he became severely depressed and began acting strangely.

Youssef said Camden Nicholson was “taking weed, definitely on lots of steroids, watching lots of porn” and previously had “made contact with some escort services.”

The couple were able to track him to a hotel where he had been running up charges on his father’s credit card, Youssef said.

“He ... started giving away $1,000 tips, according to the father,” Youssef said. “In some instances, it was totaling up to $15,000.”

After his father apparently canceled the credit card, Youssef said, Camden Nicholson sent his parents angry messages, with one reading “You’re the fakest person I know” and another saying “You people are scum, and everyone knows.”

Though the texts said not to contact him, the parents didn’t relent, Youssef said.

“Mostly they were texting him or emailing him, ‘Where are you? Come home,’” he said.

According to Youssef, Camden Nicholson had not returned to his parents’ home before Feb. 13, when they were found dead.

Around 9 that night, Camden Nicholson turned up at an emergency room in Irvine, where he made contact with police. That encounter prompted authorities to conduct a welfare check at the Newport Beach home where Richard and Kim Nicholson and Morse were already dead.

Authorities have not disclosed details about the circumstances or manner of their deaths.

Newport Beach police would not comment Thursday about anything Youssef said.

Son accused of killing parents, housekeeper in Newport Beach gated community »

Richard Nicholson was chief executive of West Pacific Medical Laboratory until it was purchased two years ago by Sonic Healthcare USA. He stayed on as a consultant through its rebranding as WestPac Labs last month

The Orange County Business Journal honored him in 2001 as one of eight Ernst & Young Entrepreneurs of the Year.

Richard and Kim Nicholson were longtime supporters of Orange County Coastkeeper, a Costa Mesa-based environmental group for which Richard was a board member for 15 years.

Camden Nicholson attended Corona del Mar High School and the University of Utah and was living in Costa Mesa, according to his Facebook profile.

Orange County-based Blue Systems International is, according to its website, “a team of former state and federal law enforcement investigators with combined experience of over 100 years.”

Daily Pilot staff contributed to this report.