def simplify_list(parent, key):
    """
    Remove trivial key and regroup it's children as a "child" property of the trivial key's parent
    Properly map empty children as 'None'

    :param parent: Dictionary containing key to simplify
    :param key: Dictionary key containing the term "*List"
    :return: simplified dictionary
    """
    child_value = parent[key]
    if child_value is not None and child_value != "0":
        child_value = [child_value[child] for child in child_value if child][0]
        if isinstance(child_value, dict) or isinstance(child_value, str):
            child_value = [child_value]
        parent[key] = child_value
    else:
        parent[key] = None
    return parent