Princess Chulabhorn, the Princess Srisavangavadhana (Thai: จุฬาภรณ; Thai pronunciation: [tɕù.lāː.pʰɔ̄ːn]; RTGS: Chulaphon; born 4 July 1957, Bangkok) is a princess of Thailand, the youngest daughter of King Bhumibol Adulyadej and Queen Sirikit, and the younger sister of King Vajiralongkorn. She is officially styled Her Royal Highness Princess Chulabhorn, which corresponds to her full Thai title Somdet Phrachao Nong Nang Thoe Chaofa Chulabhorn Walailak Agrarajakumari (Thai: สมเด็จพระเจ้าน้องนางเธอ เจ้าฟ้าจุฬาภรณวลัยลักษณ์ อัครราชกุมารี)