Every day since his son drowned on a school trip to Queensland, Hiroshi Mizuno charges the boy's phone so it does not go flat.
The last time he saw 16-year-old Taiki, his eyes were "filled with hope" as he cheerfully waved goodbye before flying out from Japan to Australia.
His son returned in a cargo hold "cold and motionless ... vacuum packed".
Taiki drowned with fellow student Shinnosuke Kimura at K'gari (Fraser Island) in March 2019 on a trip with Kanagawa University High School.
During a guided tour of the island, the group went to Lake McKenzie and students began swimming despite signs nearby warning that it was "not recommended".
Taiki and Shinnosuke were seen playing in deeper water.
The freshwater lake has a surface area of about 150 hectares and is up to nine metres deep.
A teacher later took a photo of the students at the water's edge before noticing the boys were missing.
The following morning their bodies were found by police divers.
Tour operator Huckleberry Australia has been fined $250,000 after pleading guilty to failing to comply with health and safety duties.
Heartbreaking victim impact statements from the boys' families appeared in a reserved decision handed down by magistrate John Costanzo in Brisbane Magistrates Court.
Mr Mizuno still cannot understand why his son went swimming in a lake where there are signs saying it is not recommended.
Taiki was "not the sort of boy (who) was silly, played pranks or got up to no good", he said.
Taiki wanted to become a doctor one day after losing his mother to cancer at age 13.
Mr Mizuno signed off the statement saying he would charge his "gentle, polite" son's phone again despite knowing he will never come back.
Shinnosuke's only sibling, older brother Taro, said he had bought a suit for an upcoming university entrance ceremony.
Instead he wore it at his brother's funeral.
Shinnosuke's mother Shoko wished she could "turn back time and bring the two back".
"I want to hold my son once again. I want to put him in a warm bath, and then serve him freshly cooked rice," she said in her statement.
Shinnosuke's father Yoshihiro surfed for 30 years but gave it up because his wife feared he would drown "just as Shinnosuke did".
He also misses interests he shared with his son including off-road biking.
Now Shinnosuke's off-road bike is "sitting quietly" in their garage.
Mr Costanzo said Huckleberry should have known or identified the risks with swimming at the lake.
Huckleberry failed in its duty to provide information to protect people from the risks, he said.
"Although the defendant is not charged with directly causing the deaths, the breach of duty clearly was a substantial indirect cause because it had not done any risk assessment at all, thus depriving itself and its staff or agents of crucial knowledge," Mr Costanzo said.
Huckleberry was a small company and Mr Costanzo said he was satisfied there had been some degree of financial loss due to publicity and COVID-19 since the tragedy.
Apart from the $250,000 fine, Huckleberry was ordered to pay costs of $1099.70.
A conviction was not recorded.
Mr Costanzo also recommended the Queensland government review the Work Health and Safety Act 2011 to at least include all swimming activities by tour groups.
A new sign has since been constructed at Lake McKenzie.
"Danger. Deep water beyond shoreline ... people have drowned here," it says.
