A former Scots College boy who molested children on ski trips in Canada and Australia using pornography and a 'toolbox of sex toys' has had his prison sentence almost doubled.

Ewen James Addison, who was previously jailed in Canada for molesting five to eleven-year-olds at Whistler resort, sexually abused five boys and girls in a brazen spree during visits to family homes and to Mt Hotham ski resort in Victoria.

He carried around sex toys in 'a red toolbox' and the children while swapping DVDs of Jurassic Park and Buffy the Vampire Slayer for teenage pornography.

Addison stayed with the families on holidays and sometimes took trips alone with a particular child.

Then aged in his 30s, the Scots graduate, who was sacked as the College's IT adviser and boarding house master after complaints from boys, touched the genitalia of a girl aged under 12 with both his hand and mouth.

He also reached under the sheets of a boy aged under 16 and attempted to place a vibrator between the boy's private parts.

Charged with 11 offences against five children over a period of three years from 2008 to 2011, Addison was sentenced in June last year to a maximum four years' prison with a non-parole period of two.

The sentence for nine charges of indecent act with a child under 16, and one each of indecent assault and procuring a child under 16 years to take part in an indecent act, was slammed as 'manifestly inadequate'.

The Victorian Court of Appeal increased Addison's maximum to six years, with a minimum of three years and nine months.

The state also imposed a lifetime sex offender registration over the 51-year-old, who also goes by the name James Addison.

He made international headlines back in 2003 after being charged with child sex offences at North America's largest ski resort, Whistler Blackcomb, north of Vancouver in western Canada.

Addison had moved to Canada a year earlier on a work visa and gained a part-time instructor's job with Whistler Blackcomb based on his skiing experience back in Australia.

What the Canadians did not know was that Addison had virtually fled Australia under a cloud of child sex accusations.

Addison had acted as a Scout Leader at 1st Clovelly Scout Troop from approximately 1993, and was a Scots College student from 1989; his 1993 year book said his ambition was to work as a television producer.

From 2000 to 2002, he worked in the school's IT department, also assisting in the boarding house and supervising Year 7 camp and snow trips.

He left abruptly after two students made complaints about him, and while he was never criminally charged, Apprehended Violence Orders issued in January 2002 included conditions that he not assault, molest, harass, threaten, or interfere with the two boys.

He moved to Whistler in late January 2002 and began instructing kids on holiday and learning to ski at the Whistler Kids Adventure Club, and began offending almost immediately.

On 28 April 2003, the Canadian Mounted Police arrested Addison in Whistler and charged him with nine counts of sexual abuse relating to six alleged victims.

The children ranged in age from four to eleven years old. The charges were: three counts each of sexual interference, invitation to sexual touching, and sexual assault.

At the time, Vancouver MP John Reynolds declared his intention to raise the case in the Canadian Parliament.

A Vancouver court convicted Addison on two charges, jailed him for seven months, and he returned to Australia as a registered sex offender.

Addison moved from his home state of NSW to Victoria, married in 2011, and had two children.

The locations where he preyed upon children during family social gatherings up until 2010 included the Melbourne suburbs of Chelsea and Edithvale, and Sorrento on the Mornington Peninsula.

In 2019, one of the victims, by then aged in his mid-20s, made a complaint about Addison's sexual offences.

The young man's father texted Addison in July 2019, ending their friendship and quoting a media report about the earlier sexual offending in Canada.

Between 2021 and 2023, all five Victorian victims made statements to police, who arrested and charged Addison in September 2022.

His arrest meant he had to live apart from his own children, and the family home was sold to cover legal fees and expenses.

He was sacked from his job as a sales consultant but won bail after serving 55 days behind bars.

According to court documents, Addison made a failed attempt in 2023 to prevent his name and details of his offending from being published by the media.

The Victorian County Court heard last year that despite guilty pleas to all eleven charges, Addison had shown 'no evidence of genuine remorse'.

Victim impact statements from the now adult complainants spoke of the 'devastating impact' the offending had on them.

In prison, Addison is not allowed to see his children via video calls, and is permitted telephone contact only.