The teenager who abducted, raped and murdered six-year-old Alesha MacPhail has launched an appeal against his sentence.Aaron Campbell, 16, was ordered to serve at least 27 years in prison after he was found guilty of taking the sleeping schoolgirl from her bed.He was described by the judge Lord Matthews as “cold, callous and calculating” when he was sentenced last month, and warned he may never be released.Campbell was convicted in February of a crime that shocked the UK, but only admitted his guilt in a psychological report prepared ahead of his sentencing.Alesha was at the start of a summer holiday with her father and grandparents in their home on the Isle of Bute when he snatched her from her bed at around 2am, on July 2 last year. Her mutilated body was found in woodland half a mile away, just a few hours after she was reported missing that morning. Alesha MacPhail was found dead in woodland on the Isle of ButeCredit:Facebook Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings. The Scottish Courts and Tribunals Service confirmed on Thursday that he had lodged the appeal against his sentence.Earlier this week, one of the psychologists who assessed Campbell, Dr John Marshall, called for children to be screened for psychopathic behaviour in the wake of the murder.Lord Matthews revealed that in the 12 months prior to the murder, the teenager thought about “doing something excessive”, including rape. Campbell also said in the interview that as soon as he saw the sleeping child all he thought about was “killing her”.A victim impact statement on behalf of Alesha’s grandparents, Calum MacPhail and Angela King, said they were “tortured and tormented” by her death.The killer was caught after his mother, Janette Campbell, 54, reported him to police after seeing him on her own CCTV coming and going from their home on Bute on the night Alesha disappeared. His DNA was found all over the schoolgirl’s body. A post-mortem examination revealed she had suffered 117 injuries. Campbell declared himself “quite satisfied” with the murder during the interview for the background report, and revealed that his drowsy victim asked him who he was and where he was going. He told her he was a friend of her father and was taking her home.