LOS ANGELES -- An Orange County family desperate to keep their missing daughter's name in the public eye is planning to celebrate her 20th birthday with a party at a Los Angeles-area restaurant Sunday.

Reza and Nili Jou and about 20 relatives and friends will gather at a seaside restaurant in Pacific Palisades and have invited television cameras and other journalists to the party honoring the missing San Diego State University student.

Donna Jou was 19 years old last summer when she hopped on the back of a motorcycle driven by John Steven Burgess, 35, a convicted sex criminal. That was the last time her family saw her, and brief instant messages from her phone indicate that she was locked in a bathroom and in danger at Burgess' house, her family says.

Burgess is considered a suspect, but has not been charged, in the disappearance of the Rancho Santa Margarita resident. He pleaded no contest last week in a Los Angeles courtroom to failing to register as a sex offender and was sentenced to three years in prison.

Family attorney Gloria Allred said Sunday's party is intended to keep public attention focused on the woman's disappearance.

The San Diego State University honors student was last seen by her family on June 23 as she rode away on the back of Burgess' motorcycle. She was later seen at a party at his Westside home, authorities have said.

Deputy District Attorney Christi Frey said last week that Burgess' attorney, George F. Bird Jr., "said he can't advise his client to talk about anything that might incriminate him. He still has the right to remain silent, the right not to incriminate himself. And we can't force him to talk," Frey said after the court hearing.

After Jou disappeared, Burgess abandoned his rented house and went to Florida, where he reportedly has family. His license plate and several tools that could have been used in a kidnapping were found in a Dumpster several blocks from where Jou was last seen alive.

On July 24, he was caught in Florida with cocaine and pleaded guilty to a possession charge. He was sentenced to time served and extradited to Los Angeles on the failure to register charge.

After posting bail, he returned to Florida, where he was arrested Sept. 20 on suspicion of stealing DVDs and again returned to Los Angeles, where a judge doubled his bail to $500,000.

In 2002, Burgess was convicted of three counts of battery and, the next year, he was found guilty of committing a lewd act on a child. He was sentenced to 146 days in jail, placed on three years' probation and required to register as a sex offender