I also heard that Prithibi Narayan Shah married to Magar and were rooted from Magar families. So, heard that until Tribhuvan's time, Indian monarchs would not give their daughters to Shah princes, but after Shah started marrying to Rana families, who are chhetry, Indian monarch who were very weak/powerless in India also agreed to establish relationship with Nepali monarchy who had still some future as they were the head of the state.