Sui was born and raised in Ba Sing Se since that was where her parents, Lee and Mari, met each other. At the young age of 6, Sui began showing signs of being a capable earthbender just like her mother who was once a master of earthbending. Sui trained and studied under the guidance of her mother for the next 5 years.
Since the Takara family were very successful people, Sui lived in luxury but soon tired of it. Her parents decided to enroll her in an earthbending academy to furthur improve her skills. She was one of the best thanks to the training she did with her mother. It was in the academy that she found her first and greatest rival, Tomoe Ryu. Tomoe was actually the reason why Sui strived to do her very best in the academy.
At the age of 16, Sui graduated with top honors. Along with this however, was the gradually lowering health of her father. The three of them, Lee, Mari and Sui, decided to move from Ba Sing Se to the peaceful yet lively Kyoshi Island one year later. It was there that Sui eventually mastered her earthbending.