Children start learning from the moment they arrive in the world – if not before then. What they see and hear, feel, touch and get to do starts, from the first moment, to shape their sense of the world. What is normal, and what isn’t. What’s ok, and what isn’t. These are often not things their parents have set out to deliberately teach them but things that are absorbed from their impression of the environment. To offer a more dramatic example, there’s evidence that the children of holocaust survivors experience something akin to inherited trauma.
We all have our oddities, neuroses, weaknesses, flaws, bad habits and so forth. The child growing up in a nuclear family spends those first few years in the world created by the parents. Those oddities become normal. Anything dysfunctional about the parent can become how the world works for the child. The parent who cannot show affection or give praise creates a child with low self esteem all too easily. The parent obsessed with washing, or weight management, or anything else you can think of, creates a world in which those things matter, and it is normal for them to matter. The parent who thinks boys are more valuable than girls, or who normalises domestic violence, or fat shames their child – there are so many possible examples of how a child can be set up for disaster here.
Having regular access to a number of adults has to be the way to go. The child who sees many adults will not be so persuaded that their own parent, or parents are exactly how the world works. They will see diversity, they will hear it, they will know more than one opinion is available. If they see their parents with other adults, they will be less persuaded that their parents have godlike powers, or natural authority, or are infallible or anything of that ilk. They may find people they can better identify with than their own parents. Given an array of models to emulate or reject, the child has a far better chance of finding their own identity.
Of course there are issues of power and control here. Show a child that your way is not the only way, and they might not want to do it your way. Show them that you can make mistakes, and they won’t think you’re right when you make mistakes. Let them see other parents in action and they might question how you parent. But if parenting is more about protecting the fragile ego of the adult than it is about raising a healthy child, it is pretty much a certainty that there will be problems.