How old do you think their siblings are?

[Milieva]

I mean, this was me trying to work out how old Hikaru's brothers are, but I do wonder about Kuu too.

If we take the fact they are all 14 and in 2nd year of Junior High, it must be March, and this is the end of year trip, or something. Thus why everyone is kind of bummed it's at Tokyo Tower. That means they are probably in 3rd year by the time the second arc begins, and still 14.

Our starting point is that Hikaru is 14 as long as this happens before June (June-Sept they'd be in summer uniforms).

What we know (or can ascertain): Kakeru seems to be the youngest. Masaru is the middle. Satoru is the eldest.

Kakeru is in a school uniform in the opening scenes. I would imagine this puts him somewhere between 1-3 years older than Hikaru. So he must be somewhere between 15-18. I personally would think somewhere around 16-17? So two years older?

Masaru is wearing street clothes. (I'm not sure if this is because he doesn't do the whole working in the family dojo thing, or if he is just chilling that morning.) His personality still seems very young, and energetic. So he probably is still a teenager, or at least very early 20s, but I want to put him at 18-19.

Satoru is in hakama. He just strikes me as being much older than the others. Like mid to late twenties old, which seems to suggest there is a larger gap between him and Masaru than between the other three, but perhaps his demeanor is influenced by their father having left when Hikaru was small. 

I keep debating on dropping 2-3 years between them, which would only put Kakeru in school still.

Anyone else have any thoughts on sibling ages?

[Somariel]

I headcanon Kakeru as being 2 years older than Hikaru, Masaru as 5 years older than Hikaru, and Satoru as 9 years older than Hikaru.

Also, I headcanon Kuu as being 4 years older than Fuu.

[Milieva]

See, I think Kuu couldn't be more than three years older than Fuu.

But I base this on the fact that if we take the birthdays as canon, the first series takes place in March, just after Umi's 14th birthday. (This is the only way they can all be four in second year of junior high.) My guess is this was the end of year field trip. (Not that we think CLAMP thought that through at all, because when do they ever?) So, if you add the vaguely estimated time for families to be worried about them, etcetera... It's probably been at least a month or three, so they would then be in third year of junior high, so if Kuu were four years older, she wouldn't still be in high school.

Still not sure about what I think on Hikaru's brothers, besides I think I agree with you that Kakeru is only about two years older.

[VKiera]

I have yet to write a fic where I've worked any of the siblings into it in any meaningful way, so I've no set ages in mind.

Though the stuff at the start of season 2 is in the morning right? Fuu's about to head out and Umi is having breakfast. So I guess maybe Hikaru is just working out before changing to go to school? So idk what you'd make of her and Masaru not being in uniform. If I were to write her brother's I'd agree Kakeru's about two years older, I'd put Masaru only like 18 months older than him, like they're very close in age in my head. With Satoru in his early 20s?

I'd say Kuu was in her last year of high school.

[Somariel]

See, I think Kuu couldn't be more than three years older than Fuu.

But I base this on the fact that if we take the birthdays as canon, the first series takes place in March, just after Umi's 14th birthday. (This is the only way they can all be four in second year of junior high.) My guess is this was the end of year field trip. (Not that we think CLAMP thought that through at all, because when do they ever?) So, if you add the vaguely estimated time for families to be worried about them, etcetera... It's probably been at least a month or three, so they would then be in third year of junior high, so if Kuu were four years older, she wouldn't still be in high school.

Yeah, no, that makes sense. I formed that headcanon before I knew anything about how the Japanese school year worked, so Kuu being four years older than Fuu seemed workable and hadn't really thought about it since. I think I'll probably just fudge it by giving Kuu a mid-April birthday, so she's roughly three and a half years older than Fuu.

I have yet to write a fic where I've worked any of the siblings into it in any meaningful way, so I've no set ages in mind.

Though the stuff at the start of season 2 is in the morning right? Fuu's about to head out and Umi is having breakfast. So I guess maybe Hikaru is just working out before changing to go to school? So idk what you'd make of her and Masaru not being in uniform. If I were to write her brother's I'd agree Kakeru's about two years older, I'd put Masaru only like 18 months older than him, like they're very close in age in my head. With Satoru in his early 20s?

I based my ages for Masaru and Satoru in large part on how old I think they look. Satoru looks like he's in his mid-to-late twenties at the beginning of the second arc, so that's why I put him as nine years older than Hikaru, especially since he doesn't really look different at the beginning of the epilogue.

As for Masaru, his appearance, at least to me, pretty clearly says that he's out of his teens, but he also looks at least a few years younger than Satoru, so that's why I put him as five years older than Hikaru (and therefore three years older than Kakeru). Plus, as far as I'm aware, Japanese colleges don't require uniforms, so I assumed that the reason he isn't in a uniform at the beginning of the second arc is because he's in college.