I wasn't familiar with the belief that an acorn would grant eternal youth, but I have found some references to this folklore which point to Norse or Celtic culture, rather than English - so it is possible that JM Barrie would have heard similar tales in Scotland. My feeling however is that he gave Peter acorn buttons as they would make sense with his costume made of leaves...
I found these two links:
http://www.sacredspiral.com/articles/ab/2acorn.htm
http://www.squidoo.com/grave-symbols (although this one is about tombstone symbols - scroll down)
How's your Wendy dress coming on?
Thanks for those links...I definitely know I saw something....I really wish I could find it again...this quote on one of those pages sticks out to me and may have been one of the things I read "An old British superstition states that if a person carries an acorn in her or his pocket or purse it would prevent old age."
I know it was probably not intentional by Barrie but I always found in stories things like this end up actually having some merit whether authors intended or not...like the spirit world knows and influences the stories ...if that makes any sense...or there is some collective unconscious thing going on there. I've seen stuff like that happen waaaay too much haha
I havn't even had a chance to start on the wendy costume unfortunately. I was in the middle of immigration stuff and various other time consuming and semi stressful situations. I'm hoping to get started sometime in october or november. I still have my fabric!