Jo Stickney's son Oliver is already 6'7 tall and she expects him to undergo further growth spurts before his 18th birthday next spring.
The Pocklington RUFC Colts player took up rugby when he became too big to play football, but now faces having to give up the sport he 'lives and breathes'.
Mrs Stickney cannot find a stockist that sells boots above a size 15 and has written directly to leading sportswear brands to ask them if they can manufacture studded boots to apprentice PE teacher Oliver's requirements.
So far, they have all said that producing size 16 footwear is not financially viable, and she now hopes professional rugby clubs may be able to persuade their kit sponsors to help out.
"On my side of the family, my grandfather and uncles were all 6'4, 6'5 and Oliver has a great-uncle who was 6'9, but it has taken us aback how quickly he has grown, and he still has another year before he reaches adulthood," said Mrs Stickney, of Pocklington.
"He's really taken to rugby, he plays in the second row and he hopes to move up to the 1st XV when he turns 18. He had a big growth spurt towards the end of school and was a size 14, which was manageable as most brands, like Canterbury, stock up to a 15. But in lockdown he went from 15 to a 16 and we didn't realise we wouldn't be able to access boots any more.
"We've found out that professional teams with large players get their sponsors to manufacture them specially, but I've spent days emailing the RFU, RFL, little manufacturers - they've all said it's not viable for them. I've tried the biggest stockists like Adidas, Nike and Amazon, but hit a dead end."
For everyday shoes, Oliver wears basketball trainers, which are relatively easy to find, but formal styles are also difficult to track down; and his 11-year-old brother Ben is already a size eight and taller than Oliver was at the same age.
"We've had a response from a professional player in Australia on Instagram, and I'm hoping teams like Leeds Rhinos and York City Knights might be able to help. Pocklington Rugby Club has never had anyone so big play for them before, but the chairman has taken some calls and they're trying to help.
"We had a call from a basketball team in Hull who wanted to recruit him, but it's rugby he enjoys and he'll be devastated if he can't play any more. It's the only sport his physique lends itself to and there are other tall lads on the team, so he doesn't look out of place."
Anyone who can help Mrs Stickney find size 16 boots can contact her on [email protected]