Well, I have NO clue. I don't even know if she is a bantam or not. I picked "it" up from a farm show last week. I thought maybe 8 weeks? I REALLY want it to be a hen, and the farmer said she was a hen, but having been mislead before I would not be surprised if he was wrong. I did not even think to ask how old it was. I keep reading if it has waddles it's a boy.....eeek.
All Silkies are considered bantams, I think. I would guess yours is a few months old. The wattles and comb are not big, but your cute silkie is not finished growing. You would get more expert opinions if you posted on the silkie thread here: https://www.backyardchickens.com/t/297632/silkie-thread/32260