Do I need my children's mother to be present at immigration when leaving Thailand with my half Thai sons?

When leaving Thailand with your half Thai children, it may not be necessary for their mother to accompany you to immigration. However, having a written letter of consent from her, along with a copy of her ID, is highly recommended to avoid issues. In some cases, immigration may contact her for confirmation. If you don’t have her present, it's advisable to get the appropriate documentation from the Amphur (local district office) to ensure a smooth process. Immigration typically does not allow non-ticketed individuals into the area, but the mother can wait outside in case her presence is required.