Yes during puberty testostorone is at his peak allowing for more spontaneous erections during day and night caused by dht conversion from the high levels of testostorone.
Actually one can regrow their penis from any age if they still have a lot of foreskin, can load the penile hormone receptors with hgh, dhea, testosterone and dht, help the penile tissues produce more prostaglandin e-1 for ballooning, and power your cardiovascular system to pump more blood flow into the penis, and they can go beyond their current penile size.
If you increase another extra inch, it does requires an extra 35 cc. Blood to be pushed into the penile cylinder after ballooning effects. That is a lot of work for the cardiovascular system to send this extra amount of blood into the pressurized penile cylinders.
So, you have to look into the possible "growth" (multiplication of the hormonal receptors!) in the penis ( oops, not in the prostate for trouble!) . << this is why I suggest males not to do the pc muscle kegel exercises
as it causes more dht to be built up the prostate rather than in the penile tissues.
However for females doing kegel exercises can help with faster orgasm. This seems real unfair to us men!!
Since the penile spongy tissue is testosterone- and dht-sensitive, only increasing the density of the testosterone and dht receptors can make the penis "grow" like teenage boys in their puberty.
This means, you have to re-create a physical environment of your puberty to grow your penis beyond the existing limitation. That is, you have to increase the density of your testosterone and dht receptors in the penile tissues. Having frequently spontaneous erection of your penis like your puberty will give the penile spongy tissues a "chronic stimulation" with hgh, dhea, androtenedione, testosterone and dht.
Hope this is a helpful read.