A Florida jury has recommended that a man be sentenced to death for smothering his wife and his two stepdaughters with a plastic grocery bag. 

Alberto Sierra, 42, was handed the execution recommendation on Tuesday after jurors heard grueling details over the past month about the November 2012 triple murder that he carried out. 

He pleaded guilty to the heinous murders in August after his estranged wife, Gladys Machado, and her two daughters, six-year-old Julia Padrino and three-year-old Daniela Padrino, were found dead inside an apartment in Miami-Dade on November 13, 2012. 

Earlier that day, Sierra, Machado and the girls were at a mall when he pulled a knife on them and drove them away to the home while arguing with his wife, the jury heard. 

The pair were in the middle of a bitter separation at the time, prosecutors said. 

Sierra locked his 29-year-old wife in one room, where he bound and tortured her for hours, while her children watched on, State Attorney Abbe Rifkin told jurors. 

He later killed the three of them by suffocating them with a plastic bag. Sierra also sexually assaulted Gladys and Julia, prosecutors said.  

Sierra admitted to suffocating the three of them to death on November 10. A neighbor found their bodies inside a closet after smelling a foul odor coming from the home, CBS News reported in 2012. 

All of the 12 jurors, except for one, recommended that Sierra be put to death for Machado's murder. 

Every juror agreed that he be executed for killing Julia, and eight voted for him to face the death penalty for Daniela's murder. 

At least eight of the 12 jurors need to recommend the death penalty under Florida law. 

A Spencer hearing, or post-trial hearing in Florida capital cases, is scheduled on November 2 for Sierra. 

During that time, the defense can make one final request to have the murderer spend his life in prison instead of being sentenced to death. A judge will ultimately decide his fate.   

After recommending a death sentence for Sierra, several of the victims' loved ones shared emotional impact statements. 

Michael Padrino, Julia and Daniela's biological father, immediately got choked up on the stand. 

'I'm writing because my daughters no longer have a voice in this world. Their lives, their childhood, their innocence, their chance to grow, and every year they were supposed to live, were taken from them,' Michael said as he wiped away tears. 

'For almost 14 years, I have carried a pain that no parent should ever have to live with. 

'I picture them in my mind constantly, I recreate memories and images of who they would be today. 

'My daughters were not just names in a case. They were full of laughter, fun, and they deserved to live a long life,' he continued.   

After Michael, his son Michael Padrino Jr shared his statement. 

He was just five years old when his mother and sisters were taken from him. Michael Jr declined to go to the mall that day and stayed home with his grandmother instead. 

As he spoke about memories he had of the three of them, he broke down. His hands also trembled as he read from the paper in front of him. 

He then looked up at Sierra and said: 'And you, you took them. You know you did!' 

Sierra stared blankly back at Michael Jr, now 19,  as he began to hyperventilate on the stand. 

Prosecutors ran up to console him as one of them told him: 'It's not worth it,' and another asked that the jury be sent out. 

The tense moment ended with Michael Jr looking right at Sierra as he was escorted out of the courtroom.  

Before deciding his suggested punishment, State Attorney Abbe Rifkin told jurors that a death sentence was the only appropriate option for Sierra. 

'It might be hard. But it’s right. It’s just. And it’s time,' she told the jurors. 

Meanwhile, Sierra's lawyers asked that the jury suggest life in prison for their client because he suffered a brain injury after he was hit by a car as a child. 

'We are here to remind you he is a human being,' his attorney, Khurrum Wahid, said. 

The Daily Mail contacted Rifkin and Wahid for comment.