I found something interesting about Oshi no Ko's name
The Complicated Wordplay of "[Oshi no Ko]"'s Title that got Lost in Translation
You've likely heard that there's more to Oshi no Ko's title that meets the eye, and may have seen others breaking it down already as well, but I wanted to take the opportunity to go as in depth about it as possible because of how many layers this one title hides that all unavoidably get lost in translation:
(This breakdown is spoiler free aside the basic idol's children premise)
THE FIRST LAYER
"[Oshi no Ko]" is composed by three parts:
Oshi (推し) = the verb "to push". However, in idol slang, it refers to your favorite idol within a group. The mental image of it is that she's the one you're helping "push forward" towards stardom, so as the one pushing her, she is your "oshi", the girl you wanna push for. You may have heard the term in other anime, V-tubing, or idol culture, but it basically refers to your favorite girl in a group of idols.
No (の) = Japanese possessive particle.
Ko (子) = means "kid/s". It usually refers to young children, however, depending on the context, it can also refer to a girl of young age (like a teenager) rather than just a child or group of children.
Thus in this context, the "oshi" would be Ai, since she is Goro's oshi since the start of the episode, the girl that he's rooting for and pushing for. Which would make the title "oshi no ko" translate to "The Young Girl that is my Oshi". However, since "ko" can mean either a young girl or children, the double entendre is that the title refers not just to Ai herself, but also to her children, as you could translate it as "Children of My Oshi". So the title refers to both Ai and Aqua and Ruby at the same time to drive the parallel there exists between the two. This was confirmed by the author Akasaka Aka in a Tsutaya interview.
THE SECOND LAYER
However this goes deeper, as "Oshi" sounds incredibly similar to the word "Hoshi", which is the Japanese word for "star". And this is no coincidence or stretch, because Ai's family name is "Hoshino". It's a common Japanese surname composed by the kanji for "star" and "field" (thus "starfield", space itself dotted with stars), but the pun here is in the fact that "no" can be seen as a phonetical stand in for the possessive particle (の). Thus her name becomes "Hoshi-no Ai", or "Ai of the Stars". And "(H)Oshi no Ko" becomes "The Star Girl", or "The Children of a Star". This is symbolized in how Ai's eyes are like space with a bright star shining in the middle of them, with Aqua and Ruby inheriting a star in their right and left eyes. Thus some translations have tried to localize it as "My Star", or "My Star's Children" to try and maintain the wordplay.
THE THIRD LAYER
But we're not done yet, because there is one final layer to this. Ai's own name, "Ai", is commonly associated with the word "ai" (愛), which means "love", which is a central theme in Ai's storyline. But her name isn't written in kanji, but rather in katakana, which makes it sound more like a foreign word. And this is because "Ai" sounds like the English word "Eye", which makes the wordplay come into full circle. Because "Hoshino Ai" thus translates as "Star Eyes". And this is the story of a girl who shined as brightly as the stars in her eyes, as well as the shine of her children, who would go on, of course, to become "stars" of their own in the showbiz industry.
As a final thing, Akasaka Aka commented in his interview that he has a reason why the title is stylized as 『【推しの子】』("[Oshi no Ko]") with brackets, one that will become clear in due time.