The deadly mauling of a 9-year-old California boy is under investigation.

FOX's Tom Graham explains:

Three pit bulls will likely be euthanized after young Tyler Huston was found mauled to death in his adult sister's Yuba County trailer about 40 miles north of Sacramento.

The 9-year-old had been left alone with the dogs while his sister, Alexandria Griffin-Heady, went to work...

(Griffin-Heady) "I failed him, whether it's my fault, my dogs fault, whoever's fault, I wanted to protect him and I wanted to give him an amazing life."

Tyler had been in and out of foster care after the death of his mother. Alexandria had hoped to one day adopt the boy. Now investigators say she could face child endangerment charges. The dogs are with animal services.

Tom Graham, FOX News.

 Alexandria Griffin-Heady/Facebook
Alexandria Griffin-Heady/Facebook