That's "Mrs. Mother" to you!
"As in Thai society, so within the family itself, a child quickly learns where he or she stands in relation to the other people under the same roof. Your elders are your betters in Thai tradition and should be given due deference. Mother and father are mea and paw respectively, and the child will learn to address them as khun mea and khun paw (Mrs. Mother and Mr. Father.)"