I read somewhere recently that you become an adult when your relationship with your parents changes from them looking after you, to the other way around.. not sure I completely agree but I understand the sentiment…
For me becoming a parent a 34 (5 years ago) was a big deal.. I can remember walking out fo the hospital with our baby in the car seat thingy, with a tear rolling down my cheak thinking “wow, life will never be the same again”
I guess Mortgages/marriage/pensions all play theri part aswell..
My younger brother is also unwell at the moment (fighting the big C), and is facing a very uncertain future.. this also makes me feel very grown up for some reason (all to do with taking on responsibility for our parents if he isn’t around I s’pose?)