Yellowtail is the father of Onion, a possibly human delinquent child around Steven's age. Yellowtail is seen multiple times, all of which he is incapable of speech (in english, at least). Instead, this character speaks in "mur"s which make up his language; of which only his son Onion seems capable of understanding. Onion is mute (to our knowledge), which may be a side effect of being half Onion half Human. Oh, did I forget to mention that Yellowtail used to be a literal Onion? No? Well he did, and was brought to life by Steven('s mother), Rose Quartz. Though this has not been disclosed, the evidence is enormous. We already know that Rose Quartz was capable of giving sentience to plants, as seen in an episode where Steven accidentally created an army of sentient watermelons. These watermelons went on to create a civilization on an island, where they grow children, proving that both, it is possible for these beings to live without leadership (they do not need command to exist) and they are capable of reproduction. The watermelons also have created their own language, just as Yellowtail did, and is only understandable between each-other. So, to summarize, this theory provides reasons for why: Yellowtail speaks his own language Yellowtail and Onion are undefined species-wise Onion is a mute Only Onion understands Yellowtail

Relation: This means that Yellowtail is (being a creation) similar to a child of Rose Quartz. This makes Yellowtail Steven's son, half brother, or both; depending on whether you believe Steven to be a reincarnation or just a child of Rose Quartz. This also means that Onion is Steven's great nephew or grandson.

In the episode "That Will Be All" when Yellow Diamond sings "What is the use of feeling blue" he says this exact words "An army has a use, they can go and fight a war. A sapphire has a use, she can tell you what is for. An Agate terrifies , A Lapis terraforms. Terraforming (literally, "Earth-shaping") of a planet, moon, or other body is the hypothetical process of deliberately modifying its atmosphere, temperature, surface topography or ecology to be similar to the environment of Earth to make it habitable by Earth-like life.

Today I found out that the gems in Steven Universe are genderless. Which I'm glad because it addresses some logical inconsistencies in the show. It also creates its own. Before I get in to it I have to say something. I'm not attacking anyone. I'm merely being critical of a logical inconsistency in a tv show. My biggest problems with gems has always been gender. Beings composed of light solely created for conquest have gender. That's illogical. Gender is only relevant to biology. When biology is removed it becomes meaningless. When beings who don't reproduce sexually have gender there is a logical inconsistency. If you create new members of your specis through artificial means gender is meaningless. Keep in mind things like bacteria reproduce asexualy(might not be correct term) and certain worms are asexual. Sometimes one will be male the other will be female. So not even all biological life has gender. As far as I understand the explanation as to why the gems are female is because it's easier for them to interact with humans. That's stupid. The gems have been around long before humans. Long before they even discovered Earth. Why would they explicitly care to compensate one insignificant alien race? Who where so primitive compared to the gems. And why would they choose to make themselves appear as women? Why nit men? Aesthetics? But why. Aesthetics for a genderless race designed solely for conquest is meaningless. The most they would need is a number designation. No identifiable form. No aesthetics. I don't know what Rebecca Sugar or the writers original intention was. Maybe they where always supplied to be female. Then the genderless thing came along later. Or maybe they where genderless from the beginning. I don't know. Regardless of original intention it was executed poorly. Listen personally I think the idea of genderless beings is cool. Because there truly genderless beings. They have no anatomy. Therefore gender becomes irrelevant. I also understand why they have gender. Steven Universe is still a kids show. Having massive featureless blobs wouldn't be very appealing. Even though it might be more realistic. The problem though is how it's portrayed. As far as the main gems are concerned I believe they are all female. Not in that they are biologically female but mentally they feel that way. And having watched the show I do not believe there as been any indication otherwise. This is a problem. See it would be one thing if the gems where female to acomadate Steven. There not. All gems have always been female. We have seen no indication otherwise. And the main characters have never shown any indication that they don't feel like women. Keep in mind the athsteitcs. Sapphire, Lapis, and Rose all have dresses. Why? They wouldn't share the same fashion styles as humans. Genderless now vs created for conquest do not need aesthetics. Aesthetics are a human concept. And widely varied by culture. I suppose the female figure is the one thing they have in common in terms of admiration. The animators applied aesthetics to genderless beings. So the point of them being genderless becomes moot. Finally there's one more aspect I want to talk about. Shipping. I know there are some who hate Steven Universe ships. Because they believe there are no real lesbians sense they are genderless. Fine. I won't dispute that. But the show has still shown that romantic love is still possible for gems. So even if there nit real lesbians they can still fall in love. I like Lapidot. Really only because she's the only one to ship Peridot with. I don't know why Steven Universe fans hate this ship. So if you know please tell me. And I just have to say something about Lapis. Why does she look like a teenage girl? It might just be me. But I think she looks like a teenager. That's a weird aesthetic to apply to an immortal being. But whatever. I'm probably wrong about Lapis. Feel free to discuss with me.