In the beginning of Jeannette Walls' horrific (and true) story of her life, detailed in her memoir The Glass Castle, her father (Rex) was a good parent. He, when sober, taught his children about the sciences and how to live a fearless life.
After losing all of their money, the family gave up their nomadic lifestyle and settled down in West Virgina. Depressed and dismayed, Rex began to drink heavily and his children were required to learn to fend for themselves.
Once Rex began drinking heavily, his children began to be neglected. They were lied to about the fact that starvation and cold would bring strength. They were required to, in essence, raise themselves given their parents were far too concerned with their own lives.
Therefore, Rex's parenting skills, while neglectful, forced the children to learn to survive on their own. Their independence, while coming far too early for such young children, was forced upon them given Rex's neglect. They had no choice but to fend for themselves.