THE tragic little girl found dead in an oil drum alongside her younger sister and pregnant mum appeared in a chilling video praising her 'killer' dad.

Bella Watts, four, was filmed just two months before her death sitting in the back of a car singing a song praising her father Chris.

She says: "My daddy is a hero, he helps me grow up strong.

"He reads my books, he ties my shoes, you're a hero, through and through. My daddy, daddy, I love you."

Another disturbing video shows pregnant Shanann praising her husband as "the best thing that's ever happened to me".

Bella, her younger sister Celeste, three, and mum Shanann were found dead at an oil plant where her husband worked in Frederick, on the outskirts of Denver, Colorado.

The children were allegedly placed inside “mostly full oil tanks in order to conceal the smell", Denver 7 news reports.

Shanann's husband and the girls' dad Chris has reportedly confessed to the killings and last night appeared in court shackled just hours after shocked investigators found the bodies.

Shanann's brother has pleaded for 30 seconds alone with the "heartless psychopath responsible".

Frank Rzucek says he has been left devastated by the brutal slayings of his pregnant sister and young nieces.

He later wrote on Facebook: "I just want 30 seconds alone with that heartless psychopath. May Satan have mercy on his soul.

"Doesn't take a genius to know who was suspect. My blood is boiling and the pain and anger and sadness I have in my heart.

"Nothing, absolutely nothing, would get in my way of taking away his life like he did mine and my ENTIRE FAMILY."

The Watts family murder - what is known so far:

The bodies of Shanann and her kids have been found dumped in an oil compound

They were reportedly found hidden inside gas tanks to mask their smell

Investigators say they were killed at the family home before their bodies were moved

Prosecutors have been told they now have until Monday to file charges against Watts

Shanann had just landed a glamorous new job, which kept her away from home

The couple once filed for bankruptcy and were facing a hefty fine in court next week

Family friends say there were no signs the well-liked couple were in any kind of crisis

Chris Watts made an emotional TV appeal about his missing wife and kids

After the appeal, cops reportedly announced he had confessed to killing his family

Frankie later added: "He stole my whole world and treated them like they were trash.

"I've never been so mad, sad, enraged, hurt heartbroken, lost, and shocked in all my life.

"My sister and nieces meant the absolute world to me."

Prosecutors say they believe all the victims were killed in their home and the bodies later moved but no cause of death has yet been made public in the case.

Appearing in court last night, a shackled Watts didn't speak and looked down for much of the hearing, only making eye contact as the judge reviewed his rights.

Though formal charges have not yet been filed, it's reported he could face three murder charges and three charges of tampering with evidence.

Judge Marcelo Kopcow told prosecutors they had to file formal charges by Monday and set a date for a Tuesday hearing to review the case against Watts.

He also approved a request by the suspect's attorney that police preserve all written notes and notify the defence team before any of the autopsies are performed.

Authorities have not revealed a possible motive or other details in the case.

A judge sealed the arrest affidavit, which might have provided that information.

The couple had previously faced financial difficulties, and filed for bankruptcy in 2015 to escape credit card debts.

However, things are said to have changed recently after Shanann landed herself an $80,000-a-year job promoting health supplements and patches

The perks of her new role inlcuded a Lexus company car and paid trips to Mexico, Las Vegas and the Dominican Republic - taking her away from her family.

The young mum was on a work trip just hours before she and her children were killed sparking fears her husband felt jealous about her new job.

The children had spent the weekend at home with their father while their mother was away working, police confirmed.

On Wednesday, Watts, 33, appeared on US TV to claim he had absolutely no idea where his wife and kids had disappeared to hours before "confessing" to cops.

He was filmed outside the family home as he pleaded for the safe return of his missing family - hours before reportedly confessing to killing them.

Watts looked into the cameras as he said: "I have no idea, like, where they went. I don't feel like this is even real right now. It's like a nightmare I can't wake up from."

During the interview - now seen around the world - he told how he called in the cops after learning his house was deserted.

However, just hours later legal sources claimed he had confessed to killing his family.

Cops said Watts made the shocking confession earlier in the week, according to Denver7. The police later tweeted Watts is being held at the Weld County Jail.

The FBI and Colorado Bureau of Investigation are also investigating the incident, local legal sources told reporters on the ground.

During the interview, Watts claimed he texted his wife numerous times but didn't get any response, which he thought was odd.

He then raced home but found it empty and quickly filed a missing persons report with the cops.

He claimed: "I was trying to get home as fast as I can, I was blowing through stop lights.

"I was blowing through everything just trying to get home as fast as I can because none of this made sense.

"I don't feel like this is even real right now. It's like a nightmare I can't wake up from."

The Frederick Police Department confirmed they had made an arrest "in connection to the missing person's case" of Shanann and her daughters..