Thai family has a hierarchy with the parents at the top of it. Children are educated to always honour their parents and to thank them for the time and money spent for education. Children shall have gratitude ("KATANJOO" - กตัญญู) towards their parents. The worst insult for a Thai people is to be deemed ungrateful.
Gratitude is the first qualification of a good person in Thailand. Father and mother are to be respected and honoured. Young people shall send money to support their parents until at least they get married.