File the divorce papers when the child is in California. If he is currently in Japan, get him back here or it will be difficult. You need to rove it is in his best interests to live with you over his mother.
My name is Stephen R. Cohen and I have practiced over 38 years and can be reached at 213-819-1171. I practiced mainly in Los Angeles and Orange County, California. I am not seeking clients from existing relationships with other attorneys, and give only limited advise over the phone (the phone is primarily used to set appointments), these services do not create an attorney client relationship. I apologize for mispelling< as I am a lousy typist, My answers may offend as I do not believe in pulling punches or sugar coating the truth. Further regarding courts in other states my opinions are largely based on logic and what I think is the modern trend which is to consider the needs of the child.
Your message doesn't specify whether or not your child is here in the US or with his mother in Japan. If your wife took your son to Japan without your consent and/or she is keeping the child overseas without your consent you should consider filing a Hague Convention Petition to request the immediate return of the child. However, you should know that these type of petitions are sometimes complex and you will certainly need to retain an experienced attorney.
If on the other hand, the child is in the US you should consider filing a Request for Child Abduction Prevention Order to prevent the mother from taking the child without your consent.
Either way you don't have an easy situation because if the mother wants to fight to legally take the child to Japan with her you will be face to deal with what is known as a "Move Away" request. Most times such requests are complex and need the help of an experienced attorney.
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