Characters; they're tricky beasts. What does he/she look like? What's his/her name? What kind of clothes are preferred? Easy to get along with or a bit ornery? Fussy eater? Overeater? The list of questions goes on and on and on.....
My characters are completely fictional. Not one of them is based on anyone I've known or know now. I stay resolutely away from familiar names simply because, for me, those names come with too much baggage attached. I will not slap famous faces on my characters for the same reason.
As I work out my plot by stalking around my house and muttering darkly, (trust me it's a scary sight) characters just start popping up and I give them temporary names like "eats too much boy", "snoopy girl" "loyal but annoying wife" and "falls down a lot boy". Each name reminds me how that particular character serves the plot or is my comic relief (always popular with me) and slowly but surely everything starts to jell. Plot first, characters second.
If I've enjoyed a book I will usually play one of my favorite games called "Who Do You Cast?" which is casting famous actors as the characters. I was asked once if I could play the game with my manuscript and I recoiled at the thought.
I'm fascinated that many authors base characters on real people. I do not have this talent. For me it's all pretend!