A Man Charged with  Assault on a Minor , Early Saturday Morning , Officers responded to the Billings Clinic ER,  for a report of an infant (9 week old) with serious head trauma.  The suspect, who is not the biological father of the child was located patrol at the Vegas Hotel and detained for Detectives.  After a lengthy investigation and several interviews the suspect was arrested and charged with assaulting the infant. The infant was immediately airlifted to Denver’s Children’s Hospital.