Unless they come up with something in the investigation, I’d see this as a terrible tragedy for the father.
The one point that I was curious about - how the son got away from him was addressed when it was noted the dad’s diabetic and has foot problems due to it.
I have some problems with neuropathy myself and know it can slow a person down. I knew one woman in her 30s, diabetic, who needed a wheelchair to go any distance due to severe neuropathy.
For somebody with neuropathy, Ian sure likes to walk long distances, but can’t keep up with a six year old child.