Use her Thai passport for immigration to enter and leave Thailand regardless of the different names. Show the airline the name she use to book. Always carry both.
just make sure that your foreign passport has a stamp out. Then u come back with thai. Immigrations dont care if ur thai one doesnt have out stamp as some thais use auto gate and theres no stamp that way.
O Gorman Trevor wrong if the dad isnt thai and the mom is then yes no need to get marry but if the dad is thai and the mom isnt then no. The kid isnt thai unless they get marry
Why wont your kid have dual citizenship? If the father is thai, the kid is thai (unless u dont want that). It has nothing to do with you two being married to each other.
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