BMI of my sister and reason why I chose to cook this

My sister's weight is 50.1kg and her height is 1.58m. Using the BMI tool (http://www.hpb.gov.sg/HOPPortal/gamesandtools-article/2408), I found out that her BMI is 20.1. 

She is in low risk category and her weight is in the healthy range for her height. So, she is allowed to eat food in high fat. But since it is unhealthy, I decided to add a lot of vegetable into my dish along with prawns. Prawns are a source of protein. We are all supposed to eat a balanced diet (http://www.hpb.gov.sg/HOPPortal/programmes-article/2638). Using the article, I decided to add 8 medium prawns, some cooked vegetables and the the healthiest kind of kway teow I can find. By doing this, my sister and I can eat a balanced diet. This ensures that we are healthy and fit.