I've been thinking a lot about large family dynamics.
With four naturally spaced kids, the age difference gets pretty spread out between the oldest and youngest. Even though two children are seen as average (in some places it is even looked down upon to have more than two), in my circle of friends, many families have 3 or more kids.
I've been watching the interaction in the families whose eldest, like mine, are almost teens and getting more independent and responsible, while the youngest are still rambunctious toddlers.
It gets complicated when there are many varied needs and stages all at the same time. My son is nine years older than his baby sister, and while pregnant I thought a lot about what that would mean for them. There are definitely positive and negative aspects, but I wouldn't change what we have for anything.