And now a little girl has written a letter defending her autistic brother, after he was called 'weird'.
Six-year-old Lex wrote the letter to help other children understand autism, and why children with disabilities might act differently.
In the note, Lex said she was inspired to write the letter defending her brother after another girl in her class said he was 'weird'.
She said: 'On Monday I felt very sad because a girl in my class said that my brother was weird. My brother has autism and is not weird.'
Lex added she wants other children to be more aware of autism and other disabilities, so people realise it's ok to be different.
'I would like it if we could learn about all disabilities in schools so that everybody understands that some people are different, but we should all be treated the same', she added.
The letter was posted on Facebook by Lex's mum, Sophie Camilleri, and has since been shared over 27,000 times.
Explaining the meaning behind Lex's letter, Sophie said that even though her daughter told the other girl that her brother had autism, 'the child didn't know what this was'.
She said: 'This left Lex really upset, but from this she said she wanted to make a change, she wanted to talk about "Disability Awareness In Schools" in her next School Council Meeting, so she wrote a letter (with a little help from me with the spellings) which she handed in last Thursday.
'Im so very proud that Lex has this view and wants to change the way other children view others with disabilities. She is only 6 years old and is already part of the school council, wanting to make this change', Sophie added.
And it seems like Lex has made a change, with the post being liked 21,000 times and even being shared by the National Autistic Society, racking up another 12,000 likes.
Sarah Lambert from the National Autistic Society praised the letter, telling HuffPost UK: 'We agree whole heartedly with Lex's message, and it's incredible that, at just 6 years old, she knows that we need better understanding of autism inside and out of our classrooms.
'That's why we've been encouraging schools and nurseries around the country to sign up to our free autism resources like MyWorld.
We hope that, with access to these resources, schools can help generate a greater understanding of autism amongst staff, helpers and children.'