A relative of the mother accused in the deaths of her three teenage daughters and another woman recounted disturbing phone conversations with the Shafia family leading up to the deaths and says he warned that the father might kill one of the girls.

Mohammad Shafia, 58, his wife Tooba Mohammad Yahya, 41, and their son, Hamed Mohammad Shafia, 20, are each charged with four counts of first-degree murder in the deaths of three Shafia sisters, Zainab, 19, Sahar, 17, and Geeti, 13, as well as Rona Amir Mohammad, 50.

At their trial in Kingston, Ont. Tuesday, the court heard testimony from Yahya's relative, who had flown in from Sweden to testify.

The man wept as he recounted the last time he spoke with Zainab when he attempted to convince her not to marry a boy she had been seeing. Her family didn't approve of the relationship, but he said he was unable to convince Zainab.

Yahya's relative then said Zainab's father Mohammad tried to convince him to invite some of the Shafia women to Sweden because he believed it would be easier to drown Zainab there.

He said he refused, then he said he warned Yahya that her husband was planning to kill his own daughter. He said Yahya thanked him for the information, and it's unclear what happened after.

The judge has ordered a publication ban on the relative's identity until his testimony has concluded.

Father sobs as court watches video interrogation

On Tuesday morning, Mohammad Shafia was seen burying his face in his hands and sobbing as court was shown a videotaped interrogation of his wife.

Shafia broke down as the screen showed the investigator prodding Yahya to tell the truth.

The case was abruptly adjourned last week after one of the accused fell ill.

The judge didn't specify which accused was sick, but Mohammad Shafia was the only one of the three not in the courtroom Thursday.

When reporters asked Mohammed Shafia how he was feeling Tuesday morning as he was heading into the courthouse, he simply smiled and laughed.

The defendant was let out of the hospital Friday and sent back to jail.

The Shafia sisters and Rona Amir Mohammad were found dead inside a submerged car in June 2009 in the Rideau Canal in Kingston.

With files from The Canadian Press