Organiser Andy Toulson, who befriended Tina's family while working as a journalist in north Queensland, said 26 lanterns - one for each year of Tina's life - would be released from the beach at The Strand in Townsville. Two Queensland police detectives who worked for years on the case, Senior Sergeant Gary Campbell and Senior Constable Kevin Gehringer, are expected to attend the service. Tina's parents, Tommy and Cindy Thomas, will not be making the trip from Alabama for the memorial service. Mrs Thomas has long battled illness, which she attributes to the toll of Tina's death. "We are still trying to come to terms with this being the end," Mrs Thomas wrote on Facebook earlier this month. "I know justice will come in heaven."

Mrs Thomas also wrote about her daughter's wedding day: "The 11th of October ... was the last time 10 years ago I saw my beautiful girl's face and touched her. "She was shining with happiness and had the most wonderful smile. I wish I could close my eyes and be back there and know what I know now. Missing you so very much my angel." The family is penning a book about Tina, "all the answers and evidence, every speck of it and what we lived through," Mrs Thomas said. "We had hoped to get it written by the 10th anniversary, but as always it has had to be pushed to the 11th anniversary. We need to do it for Tina and for us too." Watson has maintained he panicked and swam to get help after Tina became distressed about 15 metres below the surface while scuba diving off the Yongala wreck, 86 kilometres south-east of Townsville.

However, Queensland police alleged Watson had turned off his wife's air supply and locked her in a "bear hug" until she was dying, before turning the air back on and swimming to the surface, leaving the novice diver to die on the ocean floor. A coronial inquest found reasonable grounds to charge Watson with murder but prosecutors accepted his guilty plea to the lesser charge of manslaughter. He served 18 months' jail in Queensland. Upon his return to the US, Watson was charged with capital murder but walked free from an Alabama courthouse after the presiding judge said there was no evidence to suggest the bubblewrap salesman intended to kill his bride. Watson remarried before serving his prison term in Queensland. He now lives with his new wife in Alabama.

Tina met Watson at university in Alabama after he, of his own admission, broke into the computer administration system and scheduled himself in several of her classes. After a fairytale wedding, the pair embarked on a two-week Australian honeymoon, staying first in Sydney, before travelling to Townsville to join a dive charter. Loading "I know she so loved the beauty [of Townsville]," Mrs Thomas said. Balloons in Tina's favourite colour purple will also be released from The Strand during the 6pm service on Tuesday.