I was thinking about red dwarf stars.
The second closest star to us is a red dwarf but we can't see it with the naked eye (or see any other red dwarf directly for that matter).
The star is Proxima Centauri, only discovered about 100 years ago. It may have a loose connection with the binary star Alpha Centauri, which to the naked eye seems to be a single star but is actually a pair.
What a marvelous story this is, to my mind. We have gradually increased our visual reach over recent centuries, and now know that very close to us there is a system of three interrelated stars. Imagine what it must be like to live there.
Moreover we now think red dwarfs are the commonest kind of star, at least in our neighborhood. Theory predicts that a small red dwarf will have a lifetime of about 2,000 billion years, and then become a blue dwarf. No-one (human or other) has ever seen one of these blue dwarfs, even through a telescope, because the universe is nothing like old enough for a blue dwarf to have formed.
Our star is a yellow dwarf and won't last very long at all in comparison.