The bulk update request #11043 is pending approval.

create implication older_brother (453) -> brother_(lore) (33926)
create implication older_brother (453) -> older_sibling (460)
create implication older_sister (190) -> sister_(lore) (33948)
create implication older_sister (190) -> older_sibling (460)
create implication older_sibling (460) -> sibling_(lore) (51630)
create implication younger_brother (192) -> brother_(lore) (33926)
create implication younger_brother (192) -> younger_sibling (186)
create implication younger_sister (164) -> sister_(lore) (33948)
create implication younger_sister (164) -> younger_sibling (186)
create implication younger_sibling (186) -> sibling_(lore) (51630)

Reason: Tagged post #5514378 with older_sister and younger_sister, found it doesn't imply either older_sibling or younger_sibling. Neither of the latter None of these general tags have any child tags.

Edit: Threw in the lore tags.

Do we need these *_brother and *_sister tags?
Would brothers_(lore)/sisters_(lore)/brother_and_sister_(lore) + younger_male/older_male (for brothers) or younger_female/older_female (for sisters) be sufficient?

Sibling relationships are lore, so these would need to be converted to lore rather than kept as general, if we plan to keep them at all.

I'm ambivalent on if they're necessary. Altogether they come in at over 1000 posts, so there is clear interest in them, but I do think they might be overly specific.

Would brothers_(lore)/sisters_(lore)/brother_and_sister_(lore) + younger_male/older_male (for brothers) or younger_female/older_female (for sisters) be sufficient?

This would produce false positives if there are other characters with an age difference present. Say, two twins interacting with a parent. This could probably be solved by adding duo to the combo search, though.

The bulk update request #11044 is pending approval.

create alias older_sibling (460) -> sibling_(lore) (51630)
create alias older_brother (453) -> brother_(lore) (33926)
create alias older_sister (190) -> sister_(lore) (33948)
create alias younger_sibling (186) -> sibling_(lore) (51630)
create alias younger_brother (192) -> brother_(lore) (33926)
create alias younger_sister (164) -> sister_(lore) (33948)

Reason: Alternative for those preferring to retire the tags.

What about posts involving more than two siblings?

beholding said:
Sibling relationships are lore, so these would need to be converted to lore rather than kept as general, if we plan to keep them at all.

I'm fine with converting the older_sibling and younger_sibling tags to lore tags. But knowing how BUR #7528 for husband and wife went, the thread would die without getting approved.

beholding said:
I'm ambivalent on if they're necessary. Altogether they come in at over 1000 posts, so there is clear interest in them, but I do think they might be overly specific.

"Because there is an interest." — Slocheze, a biased loser

Older and younger siblings are a common dynamic in media. Because TV Tropes has ruined my life™, there are several tropes I could give as examples: Annoying Younger Sibling, The Baby of the Bunch, Big Brother Bully, Big Little Brother, Childish Older Sibling, Cool Big Sis, Knight Templar Big Brother, Mature Younger Sibling, Onee-sama, Promotion to Parent.

Thinking about it, if the tags are kept, it would probably do good to alias big_sister to older_sister and the like (caution treading around 1984).

beholding said:
This would produce false positives if there are other characters with an age difference present. Say, two twins interacting with a parent. This could probably be solved by adding duo to the combo search, though.

Searching parent_(lore) parent_and_child_(lore) siblings_(lore) would get a post with a parent with their elder child and younger child just as much as it would get a post of a parent with their twin children, or parent and aunt/uncle (maybe they are the twins) with the children having an age difference. Even just searching age_difference siblings_(lore) could get twins appearing alongside an intergenerational marriage one or both of the twins may or may not be involved in. Searching older_sibling_(lore) younger_sibling_(lore) would assure that the age difference is between the siblings and not just the generations of the family or friends/acquaintances of theirs.

You're also implying that twins would not be tagged older_sibling or younger_sibling. That makes sense, but would an exception be made when the minute difference in age between them is highlighted in dialogue? There's an entire episode of Gravity Falls where the conflict between Dipper Pines and Mabel Pines is that she teases him for being her "little brother" due to being born five minutes after her.

<older/younger>_<brother/sister>_(lore) seem fine to me, in concept, the character dynamics are enough of a thing to be worth tagging, and older_male and the like don't exactly work the same as these would since, y'know, tag_group:genders.

I'm not sure if <older/younger>_sibling_(lore) would really have any utility, though. since they're added by implication they're going to be pretty meaningless. for the same reason, they wouldn't even going to be useful for nonbinary characters.