I have no children yet, but I would never consider introducing LLMs until my children reach a point of maturity where they can accurately detect sophisticated deception. Even after that, I would consider these constructs as dubious in nature, they provide no measurable benefit that isn't offset exponentially by destructive acts in the form of omission or outright dangerous lies.

The age of reason is 7-12, and varies, but generally prior to which they cannot biologically detect deception perceptually.

Given observed behavior of LLMs, you must think of LLMs as the most pathological type of liar. You don't ever give those types access to your kids when you are actually fulfill parental roles.