"The good side of having a brother with autism is that other brothers and sisters fight and we don't," says Amy. "The down side is that Andrew can't say anything to me and explain what's going on in his mind."
Amy rarely talks to her friends about her brother, she says: "People stare when we go out. I didn't like it, but I've got used to it".
So when Andrew went as a weekly boarder to Prior's Court, a specialist private school in Berkshire for five to 19-year-olds on the autistic spectrum, she was relieved for him. "I miss him but I know he enjoys it," she says. "There are lots of children all the same there, so nobody stares at him".
What she also found at Prior's Court was a group established to support siblings of children at the school. She sees around 10 others there regularly once a term, having picnics, Easter egg hunts and Christmas parties, and most recently raising more than pound;1,000 for the school in a siblings' sponsored swim. "It's nice meeting other people because their brothers and sisters have got the same problems so they know what it's like," she says.
Schools are increasingly aware of the impact of autism on a family, not just on the individual child, says Prior's Court head Paul Overton: "It's vital that the care we provide is extended to the whole family. Sibling activities foster a sense of belonging for the brothers and sisters, so they can feel more positive about their situation."
Interviews by Karen Gold