As the title says. Just to clarify, he is attending a Thai university course and claims his permission to stay will have a 12 month not 90 day validity.

11.Visa Extension - In the case of being a family member of an alien who has been permitted a temporary stay in the Kingdom for study in an educational institution according to Clauses 2.8 or 2.9 hereof

In the case of being a family member of an alien who has been permitted a temporary stay in the Kingdom for study in an educational institution according to Clauses 2.8 or 2.9 hereof (applicable only to parents, spouse, children, adopted children, or spouse’s children):

Criteria for Consideration

1. The alien must have been granted a non-immigrant visa (NON-IM).

2. The alien must have proof of relationship.

3. In the case of spouse, the relationship must be de jure and de facto; or

4. In the case of children, adopted children, or spouse’s children, said children, adopted children,
and spouse’s children must not be married, must live with the alien as part of the family, and must
not be over 20 years of age; or

5. In the case of parents, funds must be deposited in a bank in Thailand, under the father’s or the
mother’s name, of no less than Baht 500,000 for the past three months. For the first year only, the
applicant must have proof of a deposit account in which said amount of funds has been maintained
for no less than 30 days prior to the filing date.

Documents to be submitted

Application form

Copy of applicant’s passport

Copy of the passport of the alien who has been permitted to stay in the Kingdom for education
purposes

Copy of documents showing proof of relationship, such as a marriage certificate, a birth
certificate, registration of child legitimization, household registration certificate, child adoption
registration certificate, or other evidence issued by the government or relevant agency

Only in the case of Criterion (5), the applicant must attach a funds deposit certificate issued by a
bank in Thailand and a copy of a bankbook.