Every evening, Malaysian housewife Sofie nervously tunes in to the television news, hoping there are no reports of any of her compatriots killed in Syria and Iraq.

She is even more tense whenever Malaysian counter-terrorism police appear on screen with news of arrests or deaths of Malaysian suspects who joined the Islamic State in Iraq and Syria (ISIS).

The 31-year-old mother of two has good reason to be anxious: Her younger sister and only sibling Yusophin, 28, left home without any warning in September last year to join the terrorist group.

"She went missing in September. After two or three days, she WhatsApped me a photo of herself in Raqqa in Syria," Ms Sofie, who declined to reveal their full names, told The Straits Times. "She said she wants to do jihad in Syria."

Raqqa is the capital of ISIS' caliphate and where it runs its operations across Syria and Iraq.

"I watch the news every night, hoping there will be no news of Malaysians killed in Syria."

Ms Yusophin is one of 66 Malaysians, along with hundreds of women from the West, including from Europe, the United States and Australia, who have made their way to join ISIS in Syria and Iraq. Many have abandoned comfortable lifestyles and also left children behind.

Australian Jasmina Milovanov, 26, is thought to have left her home in Sydney in May and travelled to Syria. She reportedly texted her former husband to tell him that their children aged five and seven needed looking after.

Even teenage schoolgirls have been enticed. Britons Shamima Begum, Amira Abase and Kadiza Sultana, all aged 16, flew to Turkey together in February before crossing the border into war-torn Syria.

In slick videos that lure Malaysians like Ms Yusophin, ISIS paints life in Raqqa as an idyllic paradise, but the realities on the ground are grim and harsh.

Raqqa faces regular air strikes by a US-backed coalition, as well as the Syrian regime of President Bashar al-Assad. US hostage Kayla Mueller, 26, an aid worker captured by ISIS in August 2013, is believed to have died in February this year in an air strike by coalition partner Jordan.

Eleven Malaysians have died fighting alongside the militant group, according to Malaysian counter-terrorism police.

Ms Sofie believes her sister wanted to leave Syria when she first arrived, but ISIS has been brutal to deserters. Anyone caught trying to leave the group faces death.

Last December, ISIS executed at least 120 of its own militants, the majority of whom were foreign fighters trying to return home, according to the British-based Syrian Observatory for Human Rights.

"She sounded regretful, but it was very difficult for her to get out. She said there were many checkpoints," said Ms Sofie.

"She cried on the phone. We spoke for about 30 minutes."

Silence followed for the next eight months, leaving her family agonising over whether she was dead or alive until May this year, when she called to say she had married a fellow Malaysian.

"She called to say she had married Ashraf, a Malaysian, who arrived in Syria shortly after her," said Ms Sofie. Mr Ashraf, who is from Shah Alam and owned a cleaning service business, met Ms Yusophin in Malaysia through a friend.

"Now that she is married and pregnant, she (Yusophin) is determined to stay on in Syria as she has someone with her," said Ms Sofie.

Ms Yusophin told her she lives in a camp and has many new friends in Raqqa among the Asians who arrive at her camp every day.

The daily arrivals - estimated in the hundreds - are a mixture of new recruits as well as established residents who moved to her camp.

"The Asians are mostly from Malaysia, Indonesia, Thailand and the Philippines. There are one or two from Singapore, according to Yusophin," said Ms Sofie.

Ms Yusophin was once a bubbly, outgoing person with many friends. "She was a happy-go-lucky person and she didn't wear the tudung (headscarf)," said Ms Sofie.

Ms Yusophin was a chief supervisor at a popular supermarket chain. Her behaviour changed when she attended religious classes in Damansara Damai, a middle-class suburb in the state of Selangor.

Shortly after, she began wearing a headscarf to go with her jeans and shirts. Later on, she discarded her jeans and shirts and wore baggy clothes instead. Finally, her colourful clothes gave way to black garb.

"Her sudden change surprised us. When we told her to wear colourful clothes and not black all the time, she became upset with us. She felt we were trying to control her," said Ms Sofie.

Both sisters were once very close, having lost their mother when Ms Yusophin was four. They were brought up by their paternal aunt.

"After she joined the religious class, she became extreme and distant from all of us. She started hanging out with the friends who introduced her to the religious classes," said Ms Sofie.

The outgoing Ms Yusophin became glued to her cellphone, communicating with those who recruited her. "She travelled to Syria together with a married woman and her husband," said Ms Sofie.

According to counter-terrorism police, some Malaysians have taken out personal loans to get to Syria.

Ms Yusophin borrowed RM20,000 (S$7,100) to fund her trip. She flew to Istanbul in Turkey and then travelled by land to the town of Gaziantep, close to the Syrian border.

"I want so much for her to come back, even if it means she will be jailed. At least she is here, back home," said Ms Sofie. "I haven't given up hope. I shall continue to hope and pray for her safe return."