How can many stars be formed from the remains of one supernova? A supernova is the explosion of a single star; so how is it that thousands of stars can &quot;be born of&quot; that one explosion (presumably only using the unspent fuel / lighter elements of the original)? Does that also mean the stars coming from a supernova cannot possibly become supernovae themselves?
For example, according to Wikipedia, the Rosetta Nebula has about 2500 including a couple of O-type stars!

approximately 2500 young stars lie in this star-forming complex, including the massive O-type stars HD 46223 and HD 46150


Edit to reduce confusion and risk of reinforcing my false premised path of questioning: I somehow had the idea that nebulae came from single supernova explosions and that all nebulae were planetary nebulae. After research, that was an absurd understanding on multiple levels.
Stars don't &quot;come from&quot; a supernova.
Stars come from the interstellar gas in the galaxy, particularly where it is more concentrated into nebulae.
This gas is mostly hydrogen and helium, but it is &quot;enriched&quot; with heavier elements from old stars, including from stars that have exploded in supernovae. Over the billions of years since the galaxy formed, there have been many supernove which have gradually increased the amount of heavier elements in the interstellar gas.
The shockwave from a supernova can cause the gas to become squeezed and more dense, and this can trigger the gravitational collapse that leads to star formation, but the gas for those stars doesn't come from one particular supernova.
As a nebula collapses into many stars, some (the largest) will be large enough to supernovae (which can trigger subsequent periods of star formation).