It seems funny to me sometimes that we say anything is possible with DID and yet within a DID site lots of people still feel like "oddballs". So we have a bunch of people who feel like "oddballs" running around on a site kinda made for "oddballs" (No Offense Meant! Just couldn't figure out another way to put it). I dunno, it's just kinda funny to me.
I'm apologizing now for any weirdness like up above. A few of us are kinda like alter-co-hosting-soup right now. I'm fronting but my co-hosts just slide around, in and out, whenever/whatever type of thing.

Oh well.
ANYWAY, you're most certainly NOT an "oddball". In our system, some alters age, some stay the same, and some age but they don't age yearly.
--Age with Body:
Myself, I age with the body. I imagine that's largely because I've been the host for 10 or 11 years. So far the only alter who seems to age with the body is Kyra, who's the same 21 years of age as me.
--Age Yearly (once a year on birthday):
Kat is a consistent 3 years older than me, but she ages once a year, every year, just like I do. So when I turned 21, she turned 24.
Rain is a consistent 2 years older than me, also aging annually.
Valera is like Kat, a consistent 3 years older than me.
Marie seems to age annually so far (only had one b-day with her known to me), and she seems to be a consistent 8 years older than me.
--Don't Age:
Cassie has been 8 and will probably stay 8 for at least a very long time.
Lynn has stayed 2 yrs old through my last birthday, so I'm guessing she's going to stay 2 just as Cassie stays 8.
So far, Rebel has stayed 18.
I haven't been through a birthday with Cassidy yet, but seeing as how she's like a darker Cassie, I think she's going to stay 8, too.
--Age Specially:
L.C. and Luna are perfect examples of aging "oddballs". They seem to jump from "bad year" to "bad year". L.C. (and possibly Luna) came forward/"came to be" when I was 13, a very bad year for me. Unlike years where like only half the year was consistently bad, this entire year was pretty bad consistently. At first I thought L.C. would stay 13 forever, like Cassie, and she did, until my 20th birthday. That was after we'd met Mike, and I remember him asking why L.C. wasn't older when she seemed to not be your typical 13-yr-old (well, then again she wasn't typical anyway) and had memories from junior year of high school (we all share memories and don't really have blank spots, but I meant memories that she knows are her's, not mine shared with her). I hadn't noticed that she had started maturing past being 13, and that she was more like when we were a junior in high school.
So, we had what we call an "Aging Conference". All the older alters of the Group (Main if you're a Main, Secondary if you're a Secondary) get together and discuss how the alter in questions has changed, grown, matured, gained knowledge, etc. The alter in question is also allowed to present their case for why they think they should stay the same age, or why they think they should be older, or even why they might think they should be younger. L.C. presented her case, Rain, Kat, and I discussed her case, and we agreed that she was older (though we never said how much older, or what age she "should" be. That is decided/felt by the alter who's aging. They age to what feels "right" to them). And at my 20th birthday, L.C. aged from 13 years old, to being 16 years old, the age we were during junior year of high school. Junior year was the only year that was worse than the year I was 13. So it's like L.C. jumped from one bad year to the next. She and Luna have stayed 16 so far, and I think they'll be staying that age until I have another "bad year" (if I do).
Oh yeah, and we have the "Aging Conference" thing like every birthday apparently, but I only became aware/a part of it just in time for my 20th birthday.
--Unsure:
We have some alters that we either haven't been through a birthday yet (so we don't know if they age), we don't know their age anyway, or stuff like that.
With Ray, we don't really know her age. We said she was 10 because she'd been around for 10 years and reacts to many things like a 10 yr old kid (though she has the maturity of an adult dog). But it doesn't really feel right calling her 11 yrs old because she's been around for 11 years, so we might have to wait until next birthday to see if it still doesn't feel right, because if it doesn't then we'll know she's really 10 years old.
We haven't had a birthday yet with Dallas and Damone, so we don't know if they'll stay 19 or if they'll age.
We don't know anything about "Hannibal's" age or aging process (if he has one).
And we haven't had a birthday with Shay yet, so we don't know if she'll stay 20 (she is 20, right?) or if she'll age.
Hope this helps you feel less like an "oddball".