Everyone in Westeros knew that Prince Rhaegar was in love with his cousin.  The childhood of Prince and Lady Baratheon was close to each other. Lady Baratheon inherited the genes of her grandmother  Rhaelle Targaryen.  She had violet eyes, pale skin, and curly platinum white hair.  Lady Baratheon chubby. She was called the beauty of the land by others. Her family gave her the nickname "White Stag." Lady Baratheon was unaware of her cousin Prince Rhaegar's deep love and obsession.

Prince Rhaegar is determined to keep men away from his cousin.  He became angry and jealous, especially when Jaime Lannister and Eddard Stark tried to get close to his cousin.