An epileptic boy has been hospitalised in London days after the authorities confiscated his cannabis oil medication in a case that has stirred debate about the medicinal use of the illegal drug.
On Monday, Caldwell, 50, from Castlederg, Co Tyrone, Northern Ireland, flew with the boy and a six-month supply of the medication used to treat up to 100 seizures a day into the United Kingdom airport from Toronto, Canada.
Billy, from County Tyrone in Northern Ireland, was given a prescription for medicinal cannabis oil a year ago to help treat his epilepsy - the first time the drug had been prescribed by the NHS.
Ms Caldwell said: "We've now reached the point where Billy is too ill to travel to get his medication, but his medication is stored minutes away from where we're now living in London".
However, only one of the seven bottles brought into the country has been returned under an emergency exemption licence.
"Billy is in the care of medical professionals who are best placed to assess the care and treatment that he requires".
"I truly believe that somewhere in the Home Office there's someone with a heart and I truly believe that Billy was pulling on their heart strings", she added.
"My experience throughout this leaves me in no doubt the Home Office can no longer play a role, in fact play any role, in the administration of medication for sick children in our country".
Billy Caldwell, a young boy with epilepsy from Northern Ireland, has been granted his life-changing medicinal cannabis oil treatment after he ended up in hospital when it was seized in London.
Javid said the British government's immediate priority was to make sure Caldwell receives "the most effective treatment possible in a safe way".
A Home Office spokesperson said last night the department was in contact with Billy's medical team and would "carefully consider what options are available" if they advise a particular type of treatment is urgently required.
After Billy received the cannabis oil on Saturday, Ms Caldwell, from County Tyrone, said his "little body has been completely broken and his little mind".
At the time the Department of Health in Northern Ireland said cannabis had not yet been licensed in the United Kingdom as a medicine.
Speaking from the hospital yesterday she said they were "praying for a miracle".
The mother of a boy with severe epilepsy has called for a meeting with the home secretary and health secretary to talk about making medical cannabis legal for children who have similar conditions to her son.
'On his medication, which included the vital but banned THC component, he was seizure-free for more than 300 days'.
He became the first person in the United Kingdom to receive a prescription after his local GP in Northern Ireland, Brendan O'Hare, began writing scripts.