Sunrise host Natalie Barr breaks down after learning she knows the brother of one of the victims. Source: Channel 7

With her voice shaky and tears in her eyes, Barr revealed that 38-year-old Katrina Dawson’s brother is a lawyer who has worked for Channel Seven.

“I’m just finding out Katrina Dawson was the sister of a prominent barrister Sandy Dawson who has done some work at Channel Seven,” Barr said, almost struggling to get the words out.

Barr breaks down as she learns of Dawson’s identity. Source: Channel 7

“Sandy Dawson, who I know and I have friends who know. A mother of three children. I’m just finding this out this morning.”

“When you put the faces to the people who have died overnight, it’s just heartbreaking,” she added.

Ms Dawson, a barrister and mother of three children, aged eight, five and three, entered the Lindt Cafe yesterday morning to grab a coffee, reportedly part of her daily routine.

She and a colleague from their law firm Eight Selborne, who is believed to be midway through her pregnancy, were held hostage inside the cafe for 17 hours.

Barr struggled to get the words out while live on air. Source: Channel 7

A visibly shaken Barr was given a few minutes to compose herself before continuing the broadcast from a street near Martin Place.

Viewers who were moved by Barr’s distress immediately took to Twitter to sympathise with her and congratulate her on her composure.

All Seven staff were evacuated form their Martin Place headquarters which were situated directly opposite the Lindt cafe at 10.20am yesterday morning, according to Seven reporter Chris Reason.

They remain locked out from the building.