Parents who are violently abusive to their children should be euthanized and their children transferred to a healthier environment. I think it's related to pedophilia in the sense that a person who is willing to injure a child is fundamentally broken and irreparable, and does not deserve any opportunity (or wasted effort) to attempt reform. It is impossible. They've committed the act and proven themselves corrupted. A healthy person cannot commit those acts. The presence of the act itself is evidence of the defect.
Children aren't "miniature adults." They're weak, vulnerable, delicate, fragile, and in need of eternally-vigilant protection and care because they cannot protect or defend themselves. A person who is willing to harm a child the way one adult might harm another is demonstrating a capacity to willfully abuse the defenseless, the way a predator animal treats prey. An adequately-developed and capable intelligence (i.e. a healthy adult human) understands why that is wrong. Broken humans do not, and they prove it by acting that way.