To look at it in a more detailed way, here is the distribution of completed family size for people who grew up with two siblings:
Percent in each category
No children 17.2
Eight or more 1.8
The modal category is two children, so the tendency here is more to follow the current norm of two kids rather than to imitate one's parents. People are really all over the place here.
I also wondered if the correlation has changed at all over the past six decades, but I saw no evidence for it. It doesn't seem to vary across gender either.