A Woods County couple was arrested by an Oklahoma State Bureau of Investigation agent Thursday night after a lengthy investigation into the death of their adopted son.OSBI agents said the 17-year-old boy was severely handicapped after being shaken as a baby which caused him to be blind, partially deaf, mute and have to eat from feeding tubes. He was found dead in his home on April 28, 2014.Agents learned that the boy had not seen a doctor for a year and his health had been declining from several illnesses along with bed sores that grew on his body.According to the OSBI, the boy's adopted mother, Twana Smart, had not taken the boy to the doctor because "she felt if she were to have taken the boy for medical care she would have been in trouble for letting the sores get as bad as they were."The agent forwarded his information to the OU Children's Hospital child protection team, who told the agent that the child had likely been neglected, which caused his death.Twana Smart, 51, and Timothy Smart, 55 were arrested Thursday on child neglect complaints. They could face up to life in prison if convicted.The boy's father was convicted years ago of shaking him in Las Vegas.