"In my class they were telling me, 'you are going to Africa.' Mummy, what is Africa?" she said.

Melissa is six. She was born in Italy and has lived in Ireland since she was two. On Thursday 19 July, along with her twin brother Great and their mother Olivia, she is due to be deported to Nigeria, a country she has never seen.

Great is autistic. Last week, his mother Olivia abandoned her legal challenge to their deportation.

It was the second legal challenge she had taken, based primarily on the grounds that there were no facilities for the proper treatment of autism in Nigeria, and that Great and his sister would be treated as outcasts.

She lost the first case and her lawyers advised her that, although this second challenge could take another two years, she would likely lose again.

"For the past four-and-a-half years I have been fighting this case, " she says. "I cannot withstand the emotional trauma any more. With a child like this, it's very challenging. Everything is just getting harder and harder on him."

Olivia is speaking to the Sunday Tribune on her phone from her room in a hostel for asylum seekers in Killarney. Though it is 10.30pm, there is a near-constant screeching in the background.

Great is still awake and shouting about it. She can't send him to another room because there is no other room.

"What can I do? I still love him, he's my baby, " she says. "Living in one room makes it worse. Things are really hard because I don't have the right to the things I need."

She says she applied for self-catering accommodation but was refused. The twins attend school, where Great has a special-needs assistant but he does not get the speech or occupational therapy Olivia says he needs.

Olivia believes Great's autism will be seen as "possession" or "voodoo" in Nigeria and that he and his sister will be stigmatised and possibly abused.

"Other people will feel threatened to live near or around him. There is no awareness of autism in Nigeria. The only 'treatment' is to send him to a psychiatric home where there is no treatment . . .

they just wait for him to die."

This claim is backed up by medical research. A study published in the British Journal of Psychiatry found that 82% of people in Nigeria "would not tolerate even basic social contact with a mentally ill person" and that mental illness was commonly believed to be caused by "possession by evil spirits".

Olivia worries about the impact their struggle has had on Great's twin sister, Melissa.

"She's brilliant at school . . . in all her books, the teachers say, 'excellent'. But it's really difficult because all the attention is on Great. She asks me, 'Mummy, do you love me?' I tell her of course I love her. She's a good kid."

I catch about half of our conversation because of the noise Great is making in the background.

There are no words, just a high-pitched shrieking as he apparently runs around. Olivia describes his behaviour.

"He doesn't know how to play with other kids.

He's always on his own. He doesn't want other children to come near him and if they come near him, he might hit them." When Olivia goes to Sunday mass at the local church, "he's screaming, running up to the altar. It's a lot of disgrace but what can I do? God gave me this child and I love him very much. God brought this child into the world; he knows what's best for him."

Olivia's solicitor, Kevin Brophy, has written to new justice minister Brian Lenihan requesting a review of her case. However, a Justice spokesperson said last week the minister saw no basis to revoke the deportation order issued by his predecessor, Michael McDowell.

Barring a surprise intervention by the minister, the deportation now simply depends on garda logistics: if it doesn't suit them to deport the family on 19 July, they will give Olivia another date to report for deportation.