Athenie Kalos, 18, enrolled in uni, bought some new clothes and Googled 'how to kill yourself'. She left no note or sign she was troubled. Now her heartbroken parents spend hours staring at photos trying to find the 'sadness in her eyes'

The heartbroken father of a teenage girl who took her own life three days after she graduating from high school has opened up about his daughter's mysterious final hours alone in her bedroom.

Athenie Kalos spent the evening of October 31 at her family's home in Melbourne booking herself into a barista's course, applying for university, making plans with her boyfriend and ordering clothes.

Then, out of nowhere, the 18-year-old Googled 'ways take your life' - before doing it. 

Her dad, Peter Kalos, doesn't know what led to his daughter taking her own life - and said he and wife, Yolla, even spend hours looking at photos trying to find 'the sadness in her eyes'. 

Athenie Kalos , 18, was excited for the future and spend her last night alive making plans

Athenie Kalos spent the evening of November 1 booking in a barista course, applying for university, making plans with her boyfriend and ordering clothes

Her father Peter Kalos he spent hours looking at photos trying to find the 'sadness in her eyes'

The acting teacher, in his 50s, went on to describe his very active daughter's strong sense of self (pictured: a memorial for Athenie Kalos)

'There's no smoking gun,' he said.

'We've spoken therapists and friends, but we can't find anything ... There were no drugs, she didn't have boyfriend problems, and police took her computer and all her diaries and found no reason why she did this.'

Five days before Athenie died, Melbourne exited the world's longest lockdown that lasted 111 days, from March 26 until October 27, as the city battled with a deadly second wave of coronavirus.

The restrictions effectively severed human contact with people outside the family home to curb the spread of the virus, with rules about when residents could leave their homes and who they could see.

The acting teacher, in his 50s, has spoken to therapists and believes that any underlying depression issues she had could have had were likely intensified during lockdown.

Pictured: Peter Kalos and his wife Yolla. Their daughter took her own life on November 1

'It's all a guessing game, and she was alone in her room when she wasn't with us during lockdown, but that time also brought us closer together as a family,' her father said.

'We would talk about her exams and helped her with pressure - we didn't care what her results were, and she did still see some friends, so there was a closeness that came with Covid-19.' 

Despite the isolation, the devoted father said his daughter was always active - making plans and seeing friends. 

'It would be different if she sat around all day or slept for long periods of time, but she didn't - whatever was going on, she obviously hid it very well.' 

Toxicology reports found no traces of substance abuse and her best friend told the family Athenie never said anything about her metal health

Through talks with therapists, Mr Kalos said he understood that any underlying depression issues she had could have had would have intensified during lockdown

Mr Kalos said his daughter was determined and had a strong sense of herself and seemed to be excited for the future with dreams of joining her older brother in the U.S, where she was born, on a gap year before university.

She also bought tickets to a concert three days before her death and had booked herself in to get a tattoo the following week.

'It's not like she knew Saturday night would be the last of her life because she made all these plans,' Mr Kalos said.

Toxicology reports found no traces of substance abuse and her best friend told the family Athenie never said anything about her metal health. 

Mr Kalos said his daughter was very comfortable with her body and her sexuality and was excited for the future

Pictured: Athenie Kalos doing gymnastics. Her parents don't know why she took her own life 

Mr Kalos said Athenie's has had an enormous impact on his family and  triggered fears for their eight-year-old son.

'We're paranoid of waking up again and finding a child dead on the ground. It haunts you, aside from the nightmare we have to go through for the rest of our lives.'

Too young to properly understand what happened to his sister, Athenie's younger brother thinks she died from coronavirus.

The father-of-three described feelings of helplessness and trauma that come with raising a child for 18 years and 'having nothing to show for it'.

Too young to properly understand what happened to his sister, Athenie's younger brother thinks she died from coronavirus

Peter Kalos said she was open with her parents and told them who she dated, when she drank and about the friends she had

'I can't look at her in pride and think "that's my beautiful daughter".' 

To help fund funeral costs and counseling services for their eight-year-old, the family started a Go Fund Me page.

'I now understand why a lot of families start charities when a loved one commits suicide, because you don't want it to be for nothing.'

He said masses of strangers had reached out to him following Athenie's death, describing their mental health struggles.

Mr Kalos said there is a stigma surrounding mental health and wants help others with suicidal thoughts.

'People worry about judgement, but I'm going to reach out to people and make it a big part of my life to tell people they don't have to suffer.' 

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