Thailand's Crown Prince Vajiralongkorn has asked the government to strip his wife's family of their royally bestowed name.It comes after seven of her close relatives were arrested in a purge of officials allegedly involved in corruption.Princess Srirasmi Akrapongpreecha is Crown Prince Vajiralongkorn's third wife, and the pair married in 2001.The move is widely expected to be a first step to divorce.He was already known to be estranged from the princess, although they continued to attend official functions together.LetterThe purge of Princess Srirasmi's family over the past 10 days has been widely reported in Thailand.However, until now the severity of the lese majeste law criminalising any critical comment about the monarchy meant that no Thai media had pointed out the family connection.The princess's uncle, a senior police general, was arrested over accusations of amassing vast wealth through smuggling and gambling rackets.Four of her siblings and two other relatives have also been held.