An investigation has been launched after a primary school sent a six-year-old girl to a GP with the WRONG grandfather.
Astonishingly, the grandfather also failed to realise he had the wrong child at the time.
And to compound the error even further, the GP also didn't realise the man had the wrong child with him and the youngster was prescribed liquid paracetamol.
The 74-year-old pensioner picked up the pupil, who has the same first name as his granddaughter and is also blonde, and took her on a mile-long bus ride to the surgery.
The grandfather, who is believed to have poor eyesight, then dropped the confused child back at Napier Primary School in Gillingham, Kent, around an hour later.
The mistake only came to light when the pupil got home and presented her parents with the medicine.
Her dad took his daughter to the Gillingham Medical Centre in Kent, where the doctor confirmed he had seen the girl earlier that day.
The girl's father, 36, who wished to remain anonymous, said on Friday 'several honest mistakes' lead to a terrifying incident, but said that he initially 'went ballistic'.
"I was boiling inside. The first thing I thought was the worst," he said.
"I had to ask my daughter the sort of questions no parent ever wants to ask, 'did he do this, did he do that'.
"When your daughter has been walked round town and taken on a bus by a strange man it makes you sick to the stomach. It's every parent's worst nightmare.
"Everyone knows to tell their children not to go with strangers but I want to tell every parent in that school - tell them again tonight."
He continued: "My daughter's been known to tell a tale or two so I took her to the surgery and the doctor said 'I saw her this morning with her grandfather'.
"It could have been worse. The doctor could have given her an insulin injection if that was what the appointment was for."
The father-of-two, a systems tester for an IT company, added: "My daughter's quite a shy girl and she's not very outspoken and she got confused.
"A little bit of pressure was put on her and she felt like it was the right thing to do to agree it was her grandfather.
"She thought it was her other grandfather who is dead. We have pictures of him up in our home so I think she got confused.
"The final check should not be to ask a child - she is only six.
"It is very strange that a grandfather would not know his granddaughter, but I understand he has poor sight.
"If he is a decent man I am sure he feels very guilty about what happened.
"Thank God it was an innocent thing done by a confused old gentleman. There were several honest mistakes."
The girl's real grandfather, her only living grandfather, said: "I couldn't believe it. The first thing I thought was Maddie McCann.
"Why are they sending someone who can't even recognise his own granddaughter to pick her up?"
The mix-up happened on Tuesday after the parents of the girl with the GP appointment called the primary school and said her grandfather would be collecting her to take her to the doctors.
A receptionist at the school took the message - but the wrong girl was presented to the grandfather. Having never seen one of her own grandfathers, the girl did not speak up.
Her parents believe the receptionist wrote down her first and second name rather than the correct surname.
Both girls are six, in the same class, are the same height and have blonde hair. The school is now reviewing its safeguarding policies.
Headteacher Zerina Slade, who called staff into a crisis meeting after the incident, said the safety of pupils was 'of the utmost importance'.
Mrs Slade said: "The safety and care of all of our children is of the utmost importance to us and we are treating this matter extremely seriously.
"As soon as we realised this had occurred, we launched an investigation. "
This has not only involved speaking to staff to find out how this could have happened, it has also involved reviewing all our procedures in connection with children's safety.
"I have also spoken with the mother of this child to offer our sincere apologies over this regrettable incident and to assure her that we are reviewing all our safeguarding policies - with the help of the council - to ensure this never happens again."
The practice manager at Gillingham Medical Centre, where the girl was taken, refused to comment.
A Kent Police spokesman said: "We have spoken to both families involved and the school.
"Technically no criminal offence had taken place, so it has been passed to social services. "If it later came to light that a crime had been committed it would be referred back to us."