The “players in” and “process of” early worldview formation for any child vary across cultural and other variables that influence the child’s upbringing (e.g., rearing communally or within a nuclear family).
The ones who supply answers to queries and facilitate the formation of a youngster’s worldview are, in a great many places, the parents and/or close family of the child. Their influence during formative years is considerable, as would be that of any other significant adults in the child’s life. Peers are important, too. And, as science is finding out, far more important than had been thought.
Along the way of gaining their worldview perspectives, youngsters hold to their formulation (assumptions/images) with varying degrees of firmness and cognitive maturity. Influences in modern society (e.g., powerful television and other media; “popular culture”) more and more have some bearing on both the process and outcome.