He really has no evidence and it is doubtful that a court would recognize him even if he does petition the courts, after all what could he claim ??
I would suspect it would be a waist of time and money and suggest he would be better served helping him find support for the problems he is going through.
I can understand your concern but at this stage she has her right to privacy and theres not much that can be done even if she is pregnant and it is his.
Just try to be there as support and if he needs to talk he's welcome at the forum. ( Dad or not

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