A toddler has become "locked in her own body" after developing a rare genetic condition.
Isabelle Barnett, two, had just learned to say her first word "Daddy" when she lost the ability to talk as she has Rett Syndrome.
"We've been told she'll never walk, talk or use her hands," said Isabelle's mother Jenny Barnett, 28.
"Being sad isn't going to help Isabelle in any way. We've got to think of the good stuff that is ahead of her, not the stuff she can't do."
Isabelle Barnet, two, (right) with her sisters Maisy, five, and Matilda, three
Isabelle was a perfectly healthy baby for the first year of her life.
Her family described her as a content child who never cried and enjoyed playing with her older sisters Maisy, five, and Matilda, three.
But after her first birthday in February 2014 Isabelle started to change.
"Isabelle started to wring her fingers and tap her hands together," said Barnett.
"She never used to cry and suddenly she was crying all the time.
"The only word she could say was 'Daddy' but she would babble all the time.
"But that went completely over a period of five months.
"She didn't want anyone to talk to her. She would just sit by herself, she didn't want any toys by her or noise - it was really strange."
Barnett and her husband Simon, 31, from Sunderland, were so concerned they took Isabelle to Airedale Hospital in Steeton, West Yorkshire.
Eight months after symptoms started doctors confirmed Isabelle had Rett Syndrome, a lifelong neurological disorder, and she would never be able to walk or talk again.
Barnett was devastated and was unable to eat or stop crying for days.
"At nighttime when I go to bed I'm by myself and I have time to think," she said.
"Everybody has their moments where you break down and realise how bad it is."
Rett syndrome affects one in every 10,000 to 12,000 women and is caused by a mutation in a gene found in an X chromosome.
The condition causes severe mental and physical disability and can even lead to scoliosis and epilepsy.
Isabelle has lost the ability to talk and move her hands and fingers purposefully – just a few months after she had developed the skills.
There is no cure and Isabelle may never be able to communicate verbally with her family again.
Her mother said: "Since she turned 13 months Isabelle has changed completely.
"She was crying a lot because she was feeling really frustrated.
"She didn't know what was happening to her because she was losing everything she could do, like talking or holding and touching toys.
"Now she almost two years old she can pick a really light tiny toy up for two seconds but she can't do anything with it – she'll just drop it a second later.
"She's locked in her own body – she can think about walking or talking or holding something but her body can't do it."
Barnett has now come to terms with Isabelle's condition and is determined to provide her with the best life possible.
"Being sad isn't going to help Isabelle in any way," she said. "We've got to think of the good stuff that is ahead of her, not the stuff she can't do."
Isabelle's relationship with her two older sisters has not changed and the pair are happy to dote on their younger sister.
Barnett hopes to purchase an eye gaze machine which would allow Isabelle to communicate with others with just a look.
The machines cost £15,000.
"It's placed an enormous financial stress on us," said Barnett.
"I've got to do this for the rest of my life.
"But it is such a hard job - you don't realise until you're doing it.
"Being a carer is demanding not just physically but its emotional straining when it's your own child."
Barnett is fundraising for a gaze machine for Isabelle and to raise funds for the charity Reverse Retts, which is working towards finding a cure for the condition.
"Our biggest hope for Isabelle is to prove the doctors wrong and learn to walk and hopefully talk," said Barnett.
For more information or to make a donation visit Isabelle's GoFundMe page.