How are stars in constellations related to each other?

The only thing they have in common is that they are all part of the same patter or constellation, other than that they are not related at all. Star in a constellation may be thousands of light years apart. One stars might be less luminous but closer to the Earth, another star might be ten times as luminous but much farther, but they both come in the lines of sight of the Earth, which is why they are all part of the constellation.