A community is in shock after police believe a 15-year old took his mother's life.
Neighbors tell us the 46 year victim: Melanie Davis was a single mother that was full of life-
    They tell us there were no signs that serious problems were going on in her household.
Everyone who knew Melanie Davis knew she loved to train for triathlons
Tanya Porter says, “She was just so happy and stayed so to her rigid schedule by her trainer and didn't miss a beat of doing everything she needed to do to try to win her challenges.”
But early Saturday morning she would not show up for a scheduled bike ride....
    The Sumner County Sheriff's Department says just after midnight they received a 9-1-1 call that a 16 year old male was awakened by a fire alarm and made a gruesome discovery.
Sheriff Sonny Weatherford says, “When he went he went to wake the family members - his mother and his brother his brother was not able to be found and his mother was covered in blood.”
When deputies arrived on the scene they found the house was full of smoke and Melanie Davis had been killed with a blunt object.
    Detectives tracked down Davis's 15 year old son by surveillance video at this Thorton's gas station and towers to find his cell phone that he threw in a field behind the Thorton's detectives arrested him walking down nearby Browns Road.
    But it was his nonchalant demeanor during a confession that detectives found strange.
Sheriff Weatherford says, “He even had a smile occasionally about some of the statements that he made but like I said it was just a bad situation.”
Tanya Porter says she has known Melanie for 5 years- they went house shopping in this neighborhood after Melanie's husband died of Lou Gherig's Disease.
    She describes Melanie's boys as sweet- both have been to her home she says she never would imagine the youngest would do something like this. 
Porter says, “You never heard of anything that she had issues with him he was just a quiet kid- didn't talk a lot not really social.”
She says now, like many others she is left with a lot of questions and several memories of a good friend.
Porter says, “My heart just breaks for them and Melanie had a lot of life in her - a lot of life in her and she was just so active.”
The Sheriff tells us the son does not have a criminal history-
    He is being held in a juvenile cell at the Sumner County Jail on suicide watch until his court date on Tuesday. UPDATE! Hendersonville Teen Accused of Killing Mom- Erica Shaffer