THE mother of Bali nine ringleader Myuran Sukumaran has revealed her pain as she waits to learn if her son will be spared from death.

"The nights are the worst time, when I go to bed," Rajini Sukumaran tells ABC TV religious program Compass tonight.

"I just can't [sleep]. I just lie there and think about all these things. Then I start praying . . . and then I fall asleep after a long time."

Sukumaran, Andrew Chan and Scott Rush are the three Australians on death row after being found guilty of trying to smuggle more than eight kilograms of heroin into Denpasar on April 17, 2005. The other six members of the gang were jailed for 20 years or life.

Melbourne barrister Julian McMahon, a member of Chan and Sukumaran's legal team, says the families remain in limbo.

"They're not allowed to grieve because no one has died," Mr McMahon tells Compass.

"They're not allowed to move on because there's hope that they might be able to save the person."