Getting a divorce wife has son in Mexico and refuses to let me bring him to U.S.

[benleon]

I am an American Citizen. I got married in the U.S. (California) to a Mexican Citizen and Legal American Resident. Our son was born here in the U.S. but during his first year born, both he and I became naturalised Mexican Citizens (dual citizens). We had plans on moving and living in Mexico so my wife and son moved to Mexico in December 2007 under my consent. We are now getting separated (I am filing for divorce - joint custody) and wife refuses to let me bring my son to the U.S. because she says he's too young (2 years and 9 months old). I have always provided for him (and her) while they've been in Mexico and have gone to see him during my vacations (I am a teacher). What legally can I do since she has control of him right now and is not giving me consent to bring him to the U.S.? Another question is can she sue me in Mexico (through Mexican courts since my son is legally a Mexican citizen) if I stop giving her child support (for refusing me access to my son here), bear in mind that I can't file the child custody paperwork since he's not in U.S. soil. I have a meeting with my attorney this Saturday and hopefully he can answer some of these questions.