The Thai spouse of a US citizen and the children of the spouse may come to the US on non-immigrant visas. These are the K3 Visa (Spouse) and K4 Visa (Children). This would permit them to finalise the process in the US. The timing is important as the K3 Visa in Thailand must have been granted to your Thai wife alternatively she must have been granted K3 status before a K4 visa can be applied for.
Filing of the Two Petitions as required for a K3 Visa in Thailand
Following this you apply for a Petition for Alien Fiancée. This is also referred to as an I-129F Form for your spouse and your children. Send off the I-129F form (petition) with supporting documents and also a copy of Form I-797 receipt notice to Homeland Security.
Once the I-129F has been approved by the USICS it will send it to the (NVC) National Visa Center. The NVC will then send your petition electronically to the embassy where you spouse is located. In other words the National Visa Center will send your petition to the US Embassy in Bangkok, Thailand.
|K1 Visa Thailand|
|K3 Visa Thailand|
|US Tourist Visa|