Now, the pair have developed a bond.

They exchange letters and occasionally phone calls, such as when she passed her exams and got into Le Moyne College - much to the bemusement of onlookers.

'Last year one lady looked at me and she was like... "oh are you waiting for a family member?" And I go... "I'm the family member, I'm sitting on his lap",' Doig said.

Asked if he checks up on whether she has been naughty or nice, McKenzie told ABC: 'Sometimes when he knows I have been a little naughty.'

The pair occasionally exchange letters and phone calls during the year (here aged 10)