The Earth does not have a second Sun, and that is why it is not discussed. The Sun is the star at the center of our solar system, and it is the primary source of light, heat, and energy for Earth. It is by far the most significant celestial body in our system.
While there are other stars in the universe, including binary star systems where two stars orbit around a common center of mass, none of them are considered a second Sun for Earth. The closest star to our solar system is Proxima Centauri, but it is still over four light-years away, making it much too distant to be considered a second Sun.
Sometimes, misconceptions or misunderstandings may arise from claims or speculative theories suggesting the existence of a second Sun or a celestial body that could mimic the Sun's effects. However, these claims are not scientifically supported or substantiated by credible evidence.
In summary, the Earth's second Sun is not discussed because it simply does not exist in reality. The Sun remains the only star that directly and significantly influences our planet.