A mum has spent several days scrubbing at her son's forehead after he got creative with his brother's Christmas present - a pen with invisible ink.
Five-year-old Louie Sheard decided to try and write his name on his face while his parents and brother Henry, nine, were playing board games in another room.
He came across the invisible pen and stood in front of a mirror to scrawl his name across the top of his head.
The child then walked in to show off his handiwork, but it was not until Henry shone a UV light from his Spy X Micro Gear Set onto Louie's head that his family saw the marking.
Claire Sheard, 40, from Welwyn Garden City, Hertfordshire, has since spent days scrubbing her little boy's head with baby oil in an attempt to wipe away the stubborn marking.
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"He came in proud as punch to show us," the mum-of-three told Jam Press. "His head looked robotic. We were all in hysterics.
"We couldn’t see anything and I asked him what he’d written with as there was nothing there so he went back into the lounge, retrieved the offending pen and brought it back to us.
"Henry then started laughing as it was his pen and clocked the situation before me and my husband did. We found it so funny."
After having a good laugh about the situation, Claire took her son to the bathroom to try and clean him up but found nothing would do the trick.
She continued: "Once we’d finally calmed down I asked Louie what he was trying to do and that’s when he said he was trying to write his name.
"You can make out the L, O and I if you look closely.
"We tried wet wipes and baby oil to remove it but to be honest I wasn’t too worried as hoped it would fade after a few days. At least you can’t see it to the naked eye.
"It was like seeing something from a superhero movie.
"Louie thinks he a pretty cool dude and very proud of himself. Although he knows not to do it again."
Exasperated at the stubborn ink, the banking assistant took to Facebook to ask for advice.
Her post has racked up 1,000 likes, with Claire captioning it: "Any thoughts on how to remove spy pen invisible ink?
"Only visible in fluorescent light? Asking for a friend. It does not wash off with soap & water!".
Hundreds of social media users have offered advice to the mum, with many left in stitches at the hilarious situation.
"Micellar water or any makeup remover, don't use harsh and dangerous products on child's face as he might get a really bad allergic reaction. Good luck," wrote one person.
A fellow mum, who had found herself in the same position, wrote: "Baby oil and warm baths with soapy water. It comes off in the end. My husband did this to my son when he was two. I did not find it amusing. Hope it comes off soon."
Others joked about how the inking suited the schoolboy and were keen to buy the product themselves.
"Looks awesome looks like he's had some kinda microchip planted in his head. On a serious note hope it wears off quick," commented someone else.
A different social media user added: "Looks amazing though I would leave it on."
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