In Princess Rambai Barni's case it was Queen Saovabha, wife of HM King Chulalongkorn (her aunt).
In 1917, after completing his studies abroad and the customary period of monasticism, Prince Prajadhipok and Princess Rambai Barni were married at Bang Pa-In Palace and given the blessings of her new brother-in-law, King Vajiravudh.
Once they inherited the throne they set about modernizing the institution of monarchy, copying European dress and customs.
The king and queen spent most of their time away from Bangkok, preferring instead to stay at the beach resort town of Hua Hin in Prachuap Khiri Khan Province at a palace called Klai Kangwon (Thai: วังไกลกังวล) (or "far from worries"), which they had built.
It was here in June 1932 that the royal couple was told of the revolution instigated by the Khana Ratsadon, which demanded of the absolutist king a constitution for the people of Siam.
The event would be a turning point for Rambai Barni and her husband, as the absolute rule of the House of Chakri was replaced by a constitutional regime.
The King played a role in the coup d'état of April 1933 where the House was ordered to close by the Prime Minister.
But Khana Ratsadon's military wing leader Phraya Phahol Phonphayuhasena ousted the government and restored its power.
In the Boworadet Rebellion, he mobilised several provincial garrisons and marched on Bangkok, occupying the Don Muang aerodrome.
)[4] Due to active bombing by the German Luftwaffe in 1940, the couple again moved, first to a small house in Devon, and then to Lake Vyrnwy Hotel in Powys, Wales, where the former king suffered a heart attack.
The queen and her brother, Prince Subhasvastiwongse Snith Svastivatana, made clear their Free Thai sympathies and used their connections to assist like-minded students in organising a resistance movement in the UK.
Despite not being an official member, the queen assisted the movement through fund raising and lobbying influential ministers.
Sulak Sivaraksa, a prominent conservative and monarchist, wrote that Pridi's role in the event was he protected responsible royals, and prevented the arrest of a person[5] who destroyed the evidence.
[6]: 5–6 However, when his government cannot solve the case, his political opponents quickly put the blame on him; some went so far as to branding him as the mastermind behind the assassination.
The coup, led by Lieutenant General Phin Choonhavan and Colonel Kat Katsongkhram, ousted Thamrong's government, which is the political ally of Pridi.
[8] The 1947 coup marked the return to power of Field Marshal Plaek Phibunsongkhram, and the end of Khana Ratsadon's role in Thai politics.
Additionally, former Queen Rambai Barni was returned the 6 million baht that the People Party seized.