Im looking for a sibling rivalry between a brother and a sister, probably they are step siblings that are the same age, and when their parents get married together, they gain a even bigger family, and the brother and the sister who are the oldest are the same. Where they are always competing against eachother and are always on eachothers backs, and always getting into trouble and doing crazy/wild/extreme things, and also dealing with the problems of their younger siblings. Most likely the brother is the troublemaker and the brother is always getting on the sisters nerves for doing something. They also have crushes on people?
I know this is really specific but I feel like I read something like this before but I forgot it.