Each elf on a shelf has serious business - to report back to Santa the deeds, good and bad, of their family, and also to pass on any special Christmas wishes.
Some elves have a sense of mischief, but the O'Brien's elf, Alfie, takes it to another level.
Alfie first arrived at the O'Brien's home in 2018, and takes his job of keeping Christmas spirit alive and well very seriously.
In between his nightly trips to Santa in the North Pole, however, Alfie manages to find the time to spice up the O'Brien's life - sometimes a little more than they'd hoped for.
"Sometimes Alfie can be nice and bring us lots of sweet treats, but he can also be very cheeky," mum, Carly said.
"He was particularly naughty this year when the kids woke up to find that he had cut the letters 'ELF' in their school shirts.
"We also had a couple of visits from the Grinch who turned our milk green and coloured the boys' faces green only last night."
While mum won't be sad to see the elf on the shelf go back to the North Pole on December 25, she'll be happy to see him back again in December 2022.
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