Stability analysis of HD 215152 c around the circular ML solution (see Table 5) and assuming planetary inclinations of 90° (top), 30° (center), and 15° (bottom).Blue points correspond to stable orbits, red points to unstable orbits, and white points correspond to highly unstable solutions (collision or ejection of a planet during the 1 kyr of the simulation). The two vertical black lines highlight the 2σ interval for the period of Planet c. We also highlight the location of the 5:4 resonance with Planet b and the 3:2 resonance with Planet d.