Watch: Paddy McGuinness on the challenges of parenting children with autism
The Top Gear presenter is father to eight-year-old twins Leo and Penelope and five-year-old daughter Felicity, all of whom have been diagnosed with autism and carry a Blue Badge that entitles them to disabled parking.
McGuinness told BBC Breakfast: "It's easy to point the finger at someone and go 'Do you mind? My child's autistic.' I think the best way is just to educate people.
"We had an incident where we were in a disability spot with the children and I could see this bloke were looking at me – judgemental, 'cause we were in a disabled parking spot, even though we had a Blue Badge.
"Normally I'd let it go, but I just thought 'I'm going to have to speak to this fella. I said 'Is everything okay?' He said, 'You're in a disabled spot... They don't look disabled.'
"I just thought – God! The level of ignorance sometimes. But he's probably unaware of autism or hidden disabilities. So I took a deep breath and explained it to him.
"And I think that was the right thing to do. Because if I'd gone mad and shouted – he'd have gone away upset, I'd have gone away upset, no one would have got on with it.
"I think things like that are important – to educate people."
The Take Me Out presenter is helping to promote Spectrum 10k, a campaign by researchers to find 10,000 autistic people and their families to take part in UK's largest ever study of the condition.
McGuinness said: "Every child, every person with autism is different. I've got three kids, they're all siblings, they're all totally different. Like any other kid they have days when they can be up to mischief and other days when they're angels. They're no different to any other children.
"It's just autism – living with it, the challenges that brings as a parent, you're totally unaware of that.
"It will help people with autism going forward. It's so frustrating there is one in five people in the UK with autism in employment. Things like that need to be changed because people with autism can contribute to so many things."
He added: "Every child is different and our three kids, they all have their own quirks and funny little things they do."
The TV presenter and comedian's wife Christine has previously revealed she is regularly challenged about using parking in disabled bays.
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