Initial conditions of a putative family related to (65) Cybele plotted in proper semi-major axis a_p vs. proper inclination sin I_p (top panel) and a_p vs. proper eccentricity e_p (bottom panel). The vertical dotted lines indicate mean-motion and three-body resonances affecting the orbital evolution of the simulated asteroids. The number of bodies is 3000, corresponding to a relatively large family mostly composed of multi-kilometre-sized objects.