For much of the 17 years that have passed since Napua Buckley lost her only son to leukemia, grief has largely been a private matter.

"We might have a small party at home for his birthday," says Buckley, 58. "If I’m just in my room alone, sometimes I’ll cry."

But on Monday, at the suggestion of her granddaughter, Buckley, who uses a wheelchair, boarded the Handi-Van and joined thousands of others for a public display of love and remembrance at the annual Lantern Floating Hawaii ceremony at Ala Moana Beach Park.

"This is awesome," Buckley said, as she surveyed the overflowing picnic areas near Magic Island and the seemingly never-ending streams of lantern-bearing participants still converging on the park. "I never expected so many people."

Organizers anticipated an overall turnout of 40,000 people, a lofty estimate supported by a massive marketing effort, live TV coverage, and the event’s own appeal as an open memorial that "transcends ethnic, cultural and religious boundaries" and encourages participants to honor not only those who died while serving in the military, but any departed loved one.

Buckley found the setting most appropriate for remembering her son, Leon Jr., who died in 1998 at age 12.

"He loved the water," she said. "He loved to swim. We come to the beach in the afternoon and when the sun went down, he’d still be in the water."

The event, presented each year by the Japanese Buddhist sect Shinnyo-en and the Na Lei Aloha Foundation, is highlighted by the release of thousands of lighted paper lanterns onto the ocean, a nod to the Japanese obon tradition.

Most of the estimated 6,000 participants who floated a lantern in memory of a loved one took time to decorate their vessel with personal messages, drawings and even photographs.

On her lantern, Buckley wrote personal messages to her son as well as to her grandmother, Cecilia Paia, who died in 1991, and to her mother, Annie Paia, who died in 2011.

Chris Trepanier, 62, of West Allis, Wis., lost her husband, Dennis, just four months ago.

On vacation in Hawaii with her sister, Trepanier took time on Monday to prepare a lantern in memory of the man with whom she had spent the past 31 years. And while the ritual itself may have been foreign to Trepanier, its meaning was deeply understood.

"It’s very moving because everyone has come here to express their thoughts and their concerns for their loved ones," said Trepanier, who also dedicated her float to her mother, who died 23 years ago.

In anticipation of a massive turnout, the Hawai‘i Convention Center offered free parking from 7 a.m. until midnight, and free shuttles transported participants from the center to the beach park starting at 3 p.m.

The program, once again presented under the theme "Many Rivers, One Ocean," was similar to years past, with live chants, taiko performances and music; slick video packages; an address by Shinnyo-en head priest Shinso Ito; a lighting ceremony involving Gov. David Ige, Honolulu Managing Director Roy Amemiya, Sikh Association of Hawaii Coordinator Manjit Reddick and Survivor Outreach Services Center Director Elisabeth Olsen; Jodo Mission Hawaii’s head minister, the Rev. Yubun Narashiba; and Matthew Corry, second counselor in the Church of Jesus Christ of Latter-day Saints’ Honolulu Stake presidency.

Ted Hamura, 65, walked to the park from his home in Kapahulu, saw the preparations for the event and decided on the spot to prepare a lantern in memory of his mother, Hazel, who died five years ago.

Hamura sat on a low wall at the edge of the sand and reflected on how his mother left school after the ninth grade to help raise her younger siblings and how she later worked as a seamstress to help support him and his three older siblings.

"I’m the youngest, so she always took care of me and worried about me," Hamura said. "She was very caring, very loving.

"This was my time to say goodbye to her, I guess," he continued. "I wrote her a little note on the lantern to tell her not to worry, that I’m doing OK."