Not a parent, but I was born in April, and turned 18 in year 12 in 2010. So the vast majority of year 12 I was legally an adult. If anything, it was fun being one of the oldest in the class haha. A lot of people in my year didn’t turn 18 until after graduation though, some not until early 2011, so they were 17 for all of year 12.

I wouldn’t want to be 19 in year 12, personally, just because it would look like I was held back at some point 😅