Home Alone director finally answers the one question on everyone's mind

It's been over 30 years since Home Alone's 1990 release.

And still, some fans have been baffled by one aspect of the festive blockbuster's plot.

For Scrooges out there who might need a little reminder, the film stars Macauley Culkin as mischievous youngster Kevin McCallister who, following a bust-up with his family one Christmas, wished they'd disappear.

The next day, his wish appears to have come true, after his mum, dad, brothers and sisters, uncles and aunties, and cousins head to the airport having accidentally forgotten all about him.

Only until they're half-way to Paris do Kevin's parents - played by much-loved Beetlejuice actress Catherine O'Hara and White Chicks legend John Heard - realise they've left their youngest son behind in Chicago.

Left to fend for himself, Kevin is also forced to defend his home from the claws of escaped criminals Harry and Marv (played by Joe Pesci and Daniel Stern), warding them off with a series of traps until his family eventually find their way home.

As we say, however, one particular part of the storyline has kept fans puzzled to this day - what on earth Kevin's parents Kate and Peter do for a living.

After all, they do have an absolutely colossal, multi bedroom, multi bathroom house on the plush outskirts of Chicago, with comes complete with a hefty loft and a roomy basement.

Kevin is accidentally left home on his own (20th Century Fox)

The couple can also afford to take their four children, Peter's brother Uncle Frank, his wife, and their four children off on holiday every Christmas - jetting off to Paris in the first film and both Florida and New York in the sequel.

So, the question begs to be asked - how exactly can they afford all of this luxury?

Well, even though it's never explicitly mentioned, Home Alone's director Chris Columbus allegedly did have an idea in mind of what Kate and Peter McCallister's jobs are when he was crafting the characters.

Speaking to The Hollywood Reporter ahead of the Christmas season, the filmmaker revealed that he and co-producer John Hughes had 'a conversation about' their careers at time, and 'decided on what the jobs were'.

Columbus revealed that Kevin's mum was a 'very successful fashion designer' - meaning her bronze-coloured get-ups and bouncy 90s blow-out wasn't simply a happy coincidence, but a conscious choice.

Maybe that's why the McCallister house was littered with mannequins, which Kevin subsequently used to ward off the criminals.

And speaking of Peter, he claimed the movie actually included several hints about his profession, even though nothing was ever confirmed.

Some fans have been wondering what the McCallister's do for a living (20th Century Fox)

"The father could have, based on John Hughes own experience, worked in advertising," Columbus explained. "But I don’t remember what the father did."

This hasn't stopped fans coming up with their own theories about Peter's job - though the director did point out that he's highly likely not involved in policing or law.

"Not organized crime," he added. "Even though there was, at the time, a lot of organized crime in Chicago."