Council managers managers have admitted a second mistake was made with a disabled boy's medication while he was in respite care.
Legal action is underway after Thomas Firth was not given his full dose of vital tablets while at a Leeds City Council-run home last year.
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As reported in the YEP, the 12-year-old's family say there have been problems with medicines for three consecutive years his during short respite breaks.
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An apology has already been given over the incident last year where his medication was missed and now council bosses have apologised after another mistake last month.
Thomas's mother Michelle said: "I am gobsmacked they have done it again."
Thomas has autism, Attention Deficit Hyperactivity Disorder, behavioural problems, Tourette's syndrome and hyperkinetic disorder which means he has a short attention span.
To help control his symptoms he takes three different drugs each day, five tablets in the morning and one at night in total.
If he misses doses, Thomas suffers withdrawal symptoms and his behaviour drastically deteriorates. It can take days for him to recover.
Mrs Firth, from Drighlington, said a mistake was made with Thomas's medication during a stay in a respite home in 2008, but she did not complain.
When the 34-year-old discovered another issue after a stay last year, she made a complaint to the council as Thomas suffered severe after-effects.
After an investigation, her complaint was upheld, although she and her husband Karl decided to pursue legal action, which is still ongoing.
The latest problem came to light when Thomas was on a short respite break last month.
Following a complaint, the council have now admitted the error.
A letter to Mrs Firth said: "Please accept my sincere apologies for any
discomfort or pain your son has suffered and for the distress that has been caused to your family."
It concluded: "Once again I am extremely sorry Thomas has suffered unnecessary harm and distress due to this mistake."
But Mrs Firth said: "How many more 'once agains' am I going to get?"
A council spokeswoman said: "We have apologised to Mrs Firth but cannot comment further because of legal proceedings."