@Malek ********************
A visa can not be extended. To stay in Thailand after acquiring a visa, a person can get an extension of stay. An extension of stay does not have to be the same visa classification they entered on (i.e. a person can go from a Non-B visa to an Extension of Stay based on Employment to an Extension of Stay based on Marriage).
Now, how about answering my question again:
IS this question about you, or for your friend?
Are YOU currently in Thailand now, and if so, what visa or extension of stay are you on?
AND...
Have you (or your friend) ever gotten a One Year Extension of Stay Based on Raising Half-Thai children, and if so, what documents were submitted.
If you can't answer those questions, I'll give a summery of the post and shut down commenting, because right now everyone's just guessing and making assumptions.