Dear Querist
there is two option, one is socially and second is legally.
Socially, you may approach her and her parent and try to settled the matter amicably and save this marriage and welfare of child.
secondly, the legal option, if you want to take legal action, then first of all issue a legal notice to her to bring back and if she is not return to you within notice period then you may file a RCR petition before the Family Court/District Court or file a divorce case.
but try first option first and second after that.
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