Adulthood vs 'sonhood'

When do you really grow up? At 18? When you leave home? When you start earning? When you get married? When you have children?
This has puzzled me a lot. Recently, I came to realize how much I am still my parents' son. Even now, approaching 30, I call them when I have any news, Good or Bad. I call them when I feel confused, I call them when I feel that I need someone I can trust to give an opinion.
Don't get me wrong, I do not always follow their advice or agree with what they say. Ever since my teenage, I have resisted advice fom my parents, but even now, I feel the need to know what they think of my plans, to know whether they agree or not, to know what their point of view is.
When it comes to sharing good news, it is much more straight forward to figure out. My parents will always be proud of their son and I can always count on them for unadulterated joy in my success. In some ways, it is a cycle. I feel happy, so I tell them, they feel happy knowing that I am happy, which in turn makes me feel happy that they are happy about me feeling happy.

Like I said, it is straight forward.

In my mind, I try to rationalise - I am soon going to be 30 years old - an age which I thought I will never get to (God, thirty years old - that feels so... well, so old). But what is my mental age? How old do I THINK I am? Sometimes 10, mostly 16-18, sometimes about 25 - no more. Is this why I still feel very much my parents' son? Should I act and feel more mature? Is it a defence mechanism against acknowledging my true age? If I still feel like a son, then does it mean I am let off being a 'proper' adult?

I remember my Grandmother's death - she was the stereotypical grandmother - cuddly, sweet, full of smiles and hugs and unconditional love. When she died in her 80s, I remember my mother sounding very lonely over the telephone. Lonely at the age of 55, married with two adult sons.

I think I can understand that. Probably, she felt the same - maybe with my grandmother's death, my mother lost a dimension of her existence - she lost her daughterhood.

All this reminds me for some strange reason of Lord of the Flies. When the sailors find the boys in the end, Ralph weeps, he weeps for the end of innocence and the darkness of man's heart and the loss of a true, wise friend. Maybe that is what I am trying to avoid. I cling on to my sonhood for it means there is still innocence in me, for it means there is still someone to protect me from the darkness in my heart and there are still friends who are true and wise, who will be happy for me no matter what and who will always see a son in this adult(?) fast approaching 30.