Father insists to keep the boy aged 8 with him

My friend's son is living abroad with his family (wife&son) for more than 5 yrs.They are married some 10 yrs back but they were not in good terms from beginning &used to quarrel often for petty matters.Son aged now 8 yrs.Three months ago she exploded & returned to India saying that she was mentally disturbed & she needs rest for a few months & came along with her son & now staying with her parents. without informing the husband she put the son in local school.The husband never expected this as he was under the impression that she will come back but she is putting the entire blame on husband saying that he abused & used harsh words & was never kind to her from beginning.She refuses to speak to her husband though he has now realised his mistakes He has come to india to settle the issue & ready to take both to his country & put the boy in the same school there. but she is not willing to come as she is afraid.but now the child is talking to father. Husband insists that both should come &boy should stuty there.But wife is not willing to come&wants her son to study here.She says he has to relocate to india .Husband says that he is paid a very good salary in the present co & he cant think of back to india atleast for one or two yrs. But the husband is attached to the child & he is very particular that the boy should be with him, his wife is house wife .under the circustances is it possible to keep the child with father.pl guide