Luisa’s character is one that many older siblings can relate to. She is asked to carry a lot of the family’s weight, to do it without complaint, and she worries that if she can’t fulfill that request, then she has no purpose in the family or in life. This is a struggle a lot of older siblings face, and that's why this song is an anthem for people like Luisa.
Charlotte's babies are born in the barn, and they float away, to Wilbur's dismay, in a process called ballooning. The spiderlings tell Wilbur that they are using the breeze to fly away. This ballooning process is important because it reduces competition between siblings and allows for genetic diversity.
The youngest of Tolo sones Eric Bakker would have himself elected as great khan. His siblings didnt really agree leading to more divisions with the family. Kublai would call a Kurultai on his own territory in northern China and elected great khan. There were two great khans at the same time resulting in futher conflict.