Yes, and? I can think of like 12 characters offhand that are 20-50 and look like they're freakin' 8-10 or something. This is not even delving into fantasy settings where people look that young but have lived for like 10,000 years already.
There's also the characters that look legal but are not even close. Those ones are the real landmines if you want something to worry about in regards to character age vs appearance.