Here is a quick synopsis. Stardew Valley is a Farming / Dating / Sandbox Sim with RPG elements and gameplay. (Mostly.) This game is based roughly on a Super Nintendo game called Harvest Moon. Harvest Moon (Abbreviated as HM from here out) was a game published by Natsume, and featured a boy inheriting a farm, and changing it from what was essentially a dump and overgrown land into a lively and profitable ranch. You could raise livestock, have pets, and could explore. HM had four seasons, Spring, Summer, Autumn, and Winter. You could plant things year round to be sold for money, and there was different maps to explore, like the town, a forest, a ledge overlooking more forest, an underground, etc. Many events were programmed into it that occurred on certain dates, like festivals, and there were some random events like hurricanes, or an earthquake, that took place. Also, you could develop relationships with some of the females in the town through various means. Gathering things, giving them crops, speaking to them daily, etc. Eventually you could marry, and you would even have a child! At the end of the games lifespan, your efforts were evaluated and you could see how well you did. Stardew Valley mirrors this and is designed around the same theme, although they have expanded on the original idea with hundreds of improvements for an even more amazing game experience. There are lots of posts here that can provide specific info about the games development, but here is one that contains a log of an interview with ConcernedApe that provides a TON of basic info you might want to know: Q and A:What is known. Make sure to read all of it, you will probably find the answer you want.
You're welcome. I have a great interest in this game and try to be very inclusive with newcomers, because they'll eventually be playing with me anyways. Haha
I think there was a Harvest Moon style Gameboy game called "The River King" or something like that. It's possible that may have been it.
Don't forget to check out Starbound too. It's not a HM style game, but it's part of the same group of developers and you might have an interest in it as well.
Hahaha, I played Legend of the River King on Gameboy ages ago (1998!). I liked the fish tank mode I do also suggest checking out Starbound in addition to Stardew Valley. I'm so excited for both!
There was a HM game for GBA called Harvest Moon: Friends of Mineral Town. Maybe that's what you're thinking of.