Welcome, i also have two little boys at 17 weeks myself. The smaller of my boys had two floppy ears until two weeks ago then they started standing up overnight one day! i also kept the ear hair fairly short (1/4 inch maybe) and i am wondering if it had anything to do with me granting access to lamb ears which came in the previous week roughly. they love those things and cant stop chewing them until completed, maybe strengthening of the muscles in that area helped? i don't know but happy their ears are solidly up now!
they get one maybe every three or 4 days now as they are a bit rich for the diet as per whats coming out the other end
Anyway i think short hair on those little floppy ears is the best choice