Number 24 corresponds to deer, which is “veado” in portuguese - which is very similar to"viado", which is a slur for gay people persons.

The slur isn't just similar to the name of the critter — it is the name of the critter. You also see people using "gazela" (gazelle), "Bambi" (that Disney critter), "biba saltitante" (jumping… "biba", dunno what was supposed to be) as slurs for gay people, always under the "flamboyantly jumping" stereotype.

The reason it gets spelled with an "i" is that slurs and swearing often get misspelled in Portuguese. It's the same deal with boceta→buceta (pussy), caralho→caraio→carai (dick), foder→fuder→fudê (to fuck).

They're popular enough for them to have been mass-produced, as opposed to, say, just writing the text on the cake with frosting.

That's not the reason though. 24 (vinte e quatro) is the gay number because it sounds like "vim de quatro" which means something like "I came on all 4s"

If you’re not gay, you must prove it by wearing a birthday tiara and listening to nothing but Judy Garland the whole day.

Only if you are gay.

/s in case someone misses the "homophobic-phobic" joke.

What else should they get? Birthday cakes with candles that say someone else's age? That wouldn't make any sense.

are you kidding? gran was a party animal. if she got them why wouldn't I?

I was going to say, if Portuguese is like Spanish, it's "anus" without the tilde over the n, right?

There's an illegal gambling game that has been extremely popular for decades called the animal game (jogo do bicho), in which each number represents an animal. 24 is the deer (veado). There's also a derogatory word for gay men, viado. The two words sound the same. So 24 is "the deer's number" but it sounds like "the fag's number".

Viado comes from desviado, which means someone who was driven off the proper path. It's just a matter of homophony (and homophobia).

I shared it ITT, but basically:

There's that stereotype of gay people being flamboyant, and often hopping in excitement. That created a bunch of associations between hopping animals and gay people; e.g. "gazela" (gazelle), "bicha saltitante" (jumping/hopping beast), but specially "veado" (deer). Often spelled as "viado".

And there's a gambling lottery called "jogo do bicho" (critters' game, or animals' game). Illegal but extremely popular, to the point some knowledge of the game is part of the popular culture. It associates 25 animals with numbers, and #24 is "veado" / deer.

So: if 24 is veado, and veado is gay, then 24 is gay. Plop it into a macho culture, much like in the rest of Latin America, and you'll see people avoiding the number. Even for their birthdays.

Nowadays it's mostly a joke; but frankly I don't like it, it still treats gay people negatively, as if "gay" was "to be avoided". Roughly in the same level as "we did $thing but no homo!" in English, you know?

You don't have candles on your birthday cake just because you're grown up? What a sad life.

No homo, but I love to blow a big candle on my b-day.

Every birthday can be gay if you're gay enough

No, it's because of an old betting game called "jogo do bicho" (critters' game):

Check #24. "Veado" (deer), often misspelled "viado", is used as a slur for gay people.

I looked it up, and allegedly it comes from a well known gambling game about animals, in which 24 is a deer, and "deer" sounds similar to a slur.

That's what she said?

Years = anos; anus = ânus. They're spelled different. Depending on dialect they may or may not sound the same.