LP 791-18 is a cool M-dwarf (about 0.14 solar masses, 2,960 K, 0.18 solar radii), 26.5 light-years from Earth. LP 791-18 b is a planet with 1.2 Earth radii, with an orbital period of 22.8 hours, at 0.010 AU from its star, and an equilibrium temperature near 564 K, discovered in 2019 via transit. LP 791-18 d is a 0.9-Earth-mass planet, with an orbital period of 2.8 days, at 0.020 AU from its star, discovered in 2023 via transit. LP 791-18 c is a 7.2-Earth-mass planet, with an orbital period of 5.0 days, at 0.030 AU from its star, discovered in 2019 via transit.