Are vander and silco brothers?

Vander and Silco are not brothers in canon!

Neither by blood nor adoption, canonically they were not written as brothers.

Their dynamic and known history was one that could accommodate such a headcanon, which anyone is allowed to have and be attached to, but it is, factually, not canon, and asserting this fact is as simple as reading the script with a little care and taking into account the context of their relationship and the use of the word "brother" in the show:

⋆ The word is very, very commonly used with a non-literal sense in fiction and in real life.

This is a word that is historically used with a sense of unity in a cause or a community, very, very common to be used poetically, metaphorically, just all-around non-literally and what have you. Think “brothers-in-arms”, used in the military, or the French révolutionnaire motto “Liberté, Egalité, Fraternité” (liberty, equality, fraternity), or in much more casual situations such as greeting a close friend with “hey, brother”, the use of “bro”/”fam”, etc. It does not suggest a literal sibling connection or context to their relationship, and outside the use of that word, in that context, there is no indication they are literally brothers.

⋆ Familial titles were used many times symbolically in the script.

Throughout the show, many scenes make it clear such terms aren’t used to signify a familial relationship, but are simply words someone like Silco would use towards those with a shared struggle and birthplace, who partnered with him under this revolutionary cause.

He uses “sons and daughters of Zaun” to refer to Zaunites (ep. 4):

He uses “brothers and sisters” to describe people going through the hardships that came with living in the undercity (ep.9):

That being, we can safely assume he does not have an actual sibling relationship with the entirety of Zaun despite using such terms.

⋆ Characters refer to their relationship in ways people wouldn’t use with or about siblings.

It’d be unnatural for siblings to address each other as “old friend”, for example, as he did in his monologue at the start of episode 3, and how Marcus also referred to Silco in episode 2 while talking to Vander ("I ran into an old friend of yours").

Likewise, later in episode 3 Vander claims they “were” brothers, in the past tense, which isn’t something one would say about literal brothers (like how everyone, including Silco, who would be the first to avoid it, still refers to Vi and Jinx simply as sisters, despite Powder explicitly renouncing her as such) in episode 5 Jinx describes their relationship to be “like” that of brothers (interestingly, the same wording used by Jayce to refer to his relationship with Viktor, which I’ll assume we can all agree is not literally that of siblings).

These are smaller details, but it still speaks to the consistency in the script when in relation to actual siblings (blood or adopted) vs. characters using such words symbolically.

⋆ The creators never intended for the audience to consider them siblings

It’s simply a mistake from some viewers, nothing was ever intentionally inserted into the show to be read as such. So much so, people directly involved in the production like the animator below have actually joked about Vander and Silco’s relationship as being romantic, never brotherly (link):

⋆ The use of such narratives is an industry staple

Finally, it’s important to recognize how the industry is still very hostile towards the idea of relationships between men being romantic or sexual, and so it’s extremely common to use the non-literal “brother” narrative to describe these relationships as more intimate than casual friendships.

This carrd is maintained by @silcolover on twitter. DM me if you think anything should be added.

I won’t entertain or engage with bad faith arguments over it, this is not an invitation to discourse. It’s a simple explanatory source to aid the reading of their relationship, as it’s being mischaracterized in the fandom and many upsetting assumptions are being made over this mistake.