State authorities are investigating the family of "Ninja Dorian," the 5-year-old boy whose buoyant attitude lifted the spirits of hospitalized children in recent months, Division of Criminal Investigation special agent Tina Trimble says.

Authorities say the Casper Police Department asked the DCI to conduct the investigation.

Trimble declined to say what the the investigation entailed, or when it would be completed. So far, there have been no charges and no arrests of the family members, she says.

Dorian's mother, Krishelle Layton, moved him and his brother and sister from Texas late last year after doctors told her there was nothing more that could be done to treat Dorian's brain tumor, according to their "Karate Chop Cancer with Ninja Dorian" page on Facebook.

Layton spent time in Casper and her mother, Carolyn Hackworth, lives here.

Late Monday afternoon, a tearful Hackworth said she could not comment on any investigation or Dorian or his siblings. She referred questions to her attorney Mark Drury, who did not immediately return a phone call on Tuesday.

Officials with the Natrona County District Attorney's Office, when called on Monday, declined to comment to reporters.

We will bring you further details on this story as they become available.

Tom Morton and Trevor T. Trujillo contributed to this story.