Nobody probably cares but this is how I think the age order in STS goes (+ my head canons on the twins'/Timmy's mom's names)
Timmy
Because duh, he's the only lamb there.
Shaun
In that flashback cutscene at the beginning of the movie, Shaun looked the youngest (also the only one w/ defining features... for whatever reason) and even though he often acts a bit smarter than the other sheep at times, I can't imagine him being older than any of them.
Bitzer
(Had to add him cuz I felt bad excluding him </3) I'm sure everyone sees Bitzer being older than Shaun, but this just canon-izes that
But he's DEFINITELY not older than anyone else, besides Timmy obviously
Nuts
NO he's not this low (technically high) because he's a bit absent minded or anything, he's mainly here because of that beginning scene of 'Fruit & Nuts' it just felt like that feeling where even the slightest thing your younger sibling says or does gets you annoyed (coming from an older sibling) Honestly I was kinda considering switching him with Shirley but this makes more sense
Shirley
The middle child (technically). To be completely honest she's here because it just feels right. At first I thought I should make her like second oldest because of that scene with Pidsley (Locked Out) but she's just constantly being used as a hammer space drawer and trampoline IDK it just gives me middle child vibes (don't ask for a better explanation, I cant give you one </3)
Leon & Billy (a.k.a. the twins)
(F.Y.I. I think Leon is the one with the longer head and the other is Billy) Okay, they're definitely not a good enough influence to be this high up but they kind a remind me of (for lack of better comparison atm) Rodrick Heffley; trouble making older brothers who get into trouble with younger siblings and turn them into trouble making trouble makers. Also if we're getting into specifics I say Leon came out the batch first (the left one, just.. you know incase you didn't read the first bit)
Hazel
Before the movie, I don't think they really added the characters' personalities consistently (especially because of the duplicate bg sheep), soo there's not enough for me to go off of, but besides her often being the scared one she's had some moments where she seems a bit mature-er than everyone previously mentioned. At first I was thinking maybe I should put her lower cuz yk she's considered the 'timid' one, but then I thought back to Fluttershy and how shes the oldest out of the main 6 (I think? I haven't rlly watched mlp don't quote me) so now I'm using that to justify my reasoning
(it took me so long to find a good photo bc my laptop was lagging so js ignore the quality ¬¬)
Meryl (a.k.a. Timmy's Mom)
I mean she has a kid she's most likely the oldest. They all definitely respect her (more than Shaun) and treat her like the oldest (e.g. they didn't hesitate to listen to her in TFBC) soo.. self explanatory
;TLDR
Timmy because he's a lamb
Shaun because he looks younger
Bitzer because it's canon, Phelan told me
Nuts because he was annoying in one episode
Shirley because middle child syndrome
Billy & Leon (a.k.a. the twins) because they remind me of immature older siblings
Hazel because she reminds me of mature older siblings
Meryl (a.k.a. Timmy's mom) because she had a kid and the flock listen to her
