I also understand the yearnings of the mother. If I am in the situation, I will advice my friend to at least give the mother time to visit her child and limit boundaries first if he's feeling that she might take away the child fr. him. It would be better if from the moment he chose to adopt the child there was already a formal agreement so the mother could not readily protest if she wants to. But for the mean time advice your friend to take measures to let the mother at least visit the child without telling who she really is bec. the child might be confuse and probably won't understand the scenario.
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