I can scarcely remember when I did NOT have children. I just cannot imagine not having children. So when a person tries to give me advice, or tell me how experienced they are with children or teenagers, AND THEY ARE NOT A PARENT, it makes NO SENSE to me. You cannot possibly understand something you have not lived and experienced.
As far as birth, that is an entire experience in itself. Carrying the child. Fathering a child. The birth. Watching a baby grow. Their first step, their first word. There's NOTHING like it. With every year, every week, every day of your child growing, it brings a new experience, a new milestone, and sometimes a new heartache.
The teenage years are rough for both the teenager, and for the parent. Sometimes the child struggles, and they have a few bumps in the road. My oldest did. I experienced a terrible thing where my son was actually sent away for three months when he was 17 years old. EIGHT HOURS AWAY. Every Sunday I would wake up at 2am to drive clear across the state to visit with him for ONE HOUR. I was not permitted to touch him. To hug him. To comfort him. We sat across each other from a table, with a guard watching. For those three months I thought I would die. Now a person who was never a parent cannot possibly feel, or even comprehend what that does to a mother. The pain was unbearable, and a non-parent simply cannot identify. There is no other love as strong as the love of one's children. It is non-judgemental, unconditional, and everlasting. You cannot take advice from someone who never had children of their own. Never felt their feet kicking inside of them, never watched their wife's intestines being removed to the side, and being placed on the operating table during a C-section, and watching your son be lifted out and placed on your wife's chest. You just cannot. The best advice I ever received was from a 70 yr. old mother I worked with.
The same son used to dress crazy, and I was very embarrassed of him. One day he came to the office I worked at with his friend to ask for some money. I acted very cold to him, and practically pushed them out the door. After they left, this woman came to me and asked me what I was doing. She said I had obviously treated my son very coldly. Her son worked at the same office with us, and was in his 40's.
They both had a good talk with me.
Her son said to me "don't you think I drove my mother nuts with the way I dressed?". And the mother told me to never do that to my son. That I treated him poorly because I was afraid it was a reflection upon me. Little did I know was that what WAS reflecting on me was the terrible way I treated my son. He is nearly 28 years old now, and of course no longer dresses that way. It was only a temporary phase. He was just being a kid. Expressing himself. I never forgot what she said, and from that day on, never judged my son for the way he dressed again, nor commented on it. That was HIS thing. Not mine.
So in answer to your question, an older mother, with grown kids is the best one to get advice from, and definitely not a person who was never a parent. They do not have a CLUE.