Devoted Sheffield mum Lauren Cox has launched a desperate appeal to help raise money to help get her poorly son to the United States for life-changing surgery.
Miss Cox's two-year-old son Bailey Hancock was diagnosed with a brain tumour in September 2016 aged just eight months and had a specialist drain fitted to remove fluid.
But an haemorrhage caused him to stop breathing and he had to have emergency surgery to save his life.
Now, after 18 months of chemotherapy, Bailey and his family have just been dealt the devastating blow that the tumour has returned.
Miss Cox, 21, of Batemoor, said: "Bailey's condition has really taken its effect on us as a family. When he was diagnosed it turned our world upside down. We'd heard about it happening to to other people but we never thought it would happen to us.
"All I want now is the best for my son and hopefully this treatment will give him a chance for the future."
The haemorrhage halted Bailey's development and caused him to lose his vision and in October 2016 he had a long-term shunt - a hole which allows fluid to move from one part of the body to another - fitted to drain the fluid and spent a total of 12 weeks in hospital.
He began an 18-month programme of chemotherapy and he started to develop again only for his shunt to become blocked.
The brave youngster then became only the second person in the UK to have a shunt fitted in his gallbladder and his vision started to return earlier this year towards the end of his chemotherapy.
Miss Cox said doctors found the tumour had returned on an MRI scan last week and he is now due to have surgery on the tumour at Sheffield Children's Hospital on Wednesday.
"The NHS do help towards the cost of the treatment but it's only available abroad and it's going to be very expensive while we are there so we are asking for help to give my son a future," she said.
"We don't know how much it'll be yet but we've set a target of £2,000 because we wanted to start raising money straight away."
Miss Cox, who also has a five-year-old daughter - Amelia, said she had become Bailey's full-time carer since he was diagnosed.
"He has been through so much and we want to get the best possible treatment for him," she added.
"My daughter has been staying with my mum because we have just been at the hospital with Bailey all the time."
For more information or to donate visit https://www.gofundme.com/treatment-in-the-usa
Miss Cox said: "Any donations will be greatly received. We just need some help to give our son the best possible chance."