Feeling unwell, Roberta made her way out of the water, but when she looked back out to sea, she noticed her family struggling to hold their heads above the current.
It was then that she heard her family screaming.
She said: "They were screaming and crying that they were stuck. People were saying 'don't go out there'."
Brave beach goers formed a human chain to help the stranded family
80 people gathered to create the 100ft-long chain
But Roberta refused to let her family drown and swam back out to them, immediately getting swept up in the current herself.
It was at this point that other beach goers noticed the family struggling and sprung into action, creating a human chain out into the water to reach the swimmers.
According to the NWF Daily News, 80 people stretched out over 100 yards to create the chain.
Even non-swimmers were determined to help, standing in the shallows, while others stood in water up to their necks.
Jessica Simmons, who had spotted the family in trouble while relaxing on the beach with her husband, then worked her way to the end of the chain in a bid to rescue the family.
She told the newspaper: "I got to the end. I practically lived in a pool. I knew I could get out there and get them."
Jessica said she recalled thinking to herself: "These people are not dying today."
Roberta (pictured with her husband Bryan) thought she and her family were going to die
Jessica and her husband then dragged the struggling swimmers, starting with the children, towards the end of the chain, and let the rest of the rescuers pass each member of the family back to shore.
Roberta recalls: "I honestly thought I was going to lose my family. It was like 'Oh God, this is how I'm going."
Shockingly, Roberta's mother had almost died while struggling for breath in the water after suffering a heart attack.
And Jessica said she knew immediately that something was severely wrong when she reached the end of the human chain to rescue the family.
She described Roberta's mother as 'exhausted', adding that her 'eyes were rolling back in her head, telling the rescuers to save the rest of the swimmers and 'let her go'.
Roberta's mother suffered a heart attack while she was out in the water
Roberta's mother is recovering in hospital
Writing later on her Go Fund Me page, Roberta added: "While out there, my mum had a massive heart attack and actually died on us for a few minutes.
After arriving at hospital, Roberta revealed that her mum was 'unconscious for a while' and while she is now awake, she is still suffering heart and stomach problems, along with pneumonia.
The family, who say they have little income, have set up a fundraising page in a bid to raise money for Roberta's mother's treatment as she continues to recover in hospital.
When she is discharged, she will need physiotherapy and other adaptations made to the family home.
The family are hoping to raise a total of $10,000 (£7,785).