Marrero told police she was at work and Castro said he was going out on a job interview.
Neighbors said the couple moved into the home last June.
"It wasn't very clean, they're living their own lifestyle up there, but that's not my business. I just came for the leak in the bathroom," said Candace Wilkins, who was with her mother when the two saw the little girl running around in her own filth, with two unleashed dogs.
Without the leak in the home, Wilkins wouldn't have found the girl.
"She was covered in feces, it didn't look like there was anything wrong with her, she was just dirty," Wilkins said.
Court documents said a razor blade was also within reach, as well as empty beer bottles. A window was also open, with an extension cord hanging from it.
Nobody knows how long the toddler was left alone.
The toddler is staying with another family member while the Department Of Children and Families investigates.
Castro is being held on a $100,000 bond and Marrero is held on a $65,000 bond.
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