David Causey and his wife Christina spent the morning posting and handing out flyers in hopes of getting information about their missing 50-year-old aunt Rebecca Weiss.
"We're doing our best. We're trying to talk to a lot of locals," he said.
Rebecca Weiss was reported missing Saturday by her husband, Alan Weiss. He told authorities that she left their home in Marina del Rey en route to Rancho Palos Verdes, where she planned to do some diving. When she didn't return, he drove to her favorite beach and found her abandoned SUV in a parking lot, and her diving back near the shoreline.
Alan Weiss has described his wife is an avid free diver, which means the swimmer does not use a breathing apparatus.
Rebecca Weiss' mother says her daughter would never have gone diving alone.
"It's so weird for her to fall victim to the water. She's a strong swimmer," David Causey said.
Officials said homicide detectives have been assigned to the case because there are some unusual circumstances with her disappearance. Detectives plan to speak to the woman's husband in person. They said Alan Weiss is cooperating with the investigation, but they have only been talking to him over the phone.
Rebecca Weiss was described as Asian, 5 feet 5 inches tall, about 115 pounds, with black hair and brown eyes. Anyone with information was asked to contact the Los Angeles County Sheriff's Department at (323) 890-5500.