A father and son were found dead in Deltona following an apparent murder-suicide.According to the Volusia County Sheriff's Office, deputies were called to Sumatra Avenue Sunday morning.Responding deputies found 55-year-old Daniel Demarco and his son, 34-year-old Travis Demarco, dead from gunshot wounds.Investigators believe Travis killed his father and then himself."I can't believe what Travis did, you know," said Kathy Kane, neighbor. "Because Dan... he seemed like such a nice man."Kane said she met Daniel Demarco over a week ago when he moved into the neighborhood. She described him as friendly and was shocked to hear about what happened.The two were found by another resident of the home after Daniel did not respond to attempted contact."Detectives learned that Travis had been dealing with mental health issues, including a serious condition that was officially diagnosed earlier this year," a statement from VCSO reads. "His father had expressed concerns about his son's mental state and behavior and was helping him receive treatment and medication."Licensed Mental Health Counselor Zonovia Proctor said without knowing the specifics of the case, it's hard to know what led to this."It could have been completely intentional," she added. "It could have been unintentional, it could have been in crisis, it could have been because of trauma history. It could be a chemical imbalance. It could be so many things."Deputies say Travis' father was aware he was struggling mentally and he was getting help, but even that is sometimes not enough. "Ultimately, very often, it comes down to a split-moment decision when support is not there," said Proctor. "And I say decision very lightly because, again, it's die by suicide, not commit suicide. It's sometimes not an active decision. It might be an impulse at that moment. "It could also be that care was given, but it was already too late. It's important to pay attention to what the people around you are feeling. "If someone tells you that they're in distress, believe them," added Proctor. "Believe them. It's not just a cry for attention..."If they don't tell you they're suffering, but you can see it, ask. It's important to have tough conversations.There are several resources available... But right at your fingertips is the 9-8-8 number for the suicide and crisis lifeline.