A sheriff's deputy. His 10-year-old son. A bitter custody battle. A haunting death. Was it suicide? Or something more sinister? Twenty-five years later, authorities decided to take a closer look. So did Mercury News reporter Julia Prodis Sulek. Join her on a whirlwind journey from Silicon Valley to Oklahoma's cowboy country as she explores a brutal question: How did a 10-year-old boy end up hanging on the family farm?