It is all his parents can do to talk about it.
They had lost sight of Mozzie as he played with his siblings in their yard Friday afternoon. But this time, they couldn't find him. So they called 911.
"We're running around the property trying to find him," recalled Kiersten. "We kept running past the septic tank."
A Kirkland police officer who responded to the scene, too, noticed the septic tank and decided to look inside.
“He got down on his knees, and he pulled him up by the foot out of the water,” Kiersten said.
This has happened before. Two years ago, a 2-year-old Pierce County boy fell into his grandparent's septic tank and survived. In 2015, a Burlington boy, also two, was not as lucky. Like Mozzie, he drowned, too.
"It kills us," said Eddie Herrera, his father. "And it's killing me inside that my son passed away due to this. And it shouldn't have happened."
Now Herrera wants to warn others to secure their septic tank to prevent another child from suffering the same fate.
"We want you guys to know that it is dangerous," said Herrera. "Please don't hesitate. Take care of it as soon as possible. Don't wait until tomorrow because tomorrow's not promised."
Herrera says he is not angry with anyone over this. They are leaning on their faith to help them make it through.
But one thing they know for sure: They will never live in their Redmond house again.
The family has set up a GoFundMe account to help with funeral costs.