Early in Fabledom, the game teaches you that every Homestead requires a Well. If you don't have one, a blue water droplet-shaped icon will appear above the house, indicating that it lacks that connection.
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Aside from just being ugly, the blue water drop icon serves an important function in Fabledom: it lets you know that your home is not connected to a well, which lowers the desirability factor of a Homestead. This in turn lowers the happiness of an individual Fabling living in that Homestead, as well as the overall happiness of your kingdom. If your happiness drops too low, newcomers will not want to move to your kingdom, and you will not be able to reach population milestones and unlock new buildings.
However, sometimes a water drop icon will appear above a Homestead that is within the radius of a Well, which you can check by clicking on the Well. Fortunately for players, the solution is simple, and doesn't even require you to rebuild either structure.
Here's how to fix the issue of Homstead not registering a nearby well in Fabledom.