König family is 22 Myr old according to orbital evolution. The observed family (green) has a very peculiar structure in the proper semi-major axis a_p versus the proper inclination sin i_p. The synthetic family (blue; top) is initially distributed in a simple ‘ellipse’, created by an isotropic impact. The geometry of the impact was f = 85°, ω = 0°. In the course of evolution, the distribution is modified by the 𝑔 − 𝑔₅ + s − s₆ secular resonance. At the time (22 ± 2) Myr (bottom), it exactly corresponds to the observed distribution. Such a young age indicates that the SFD can still be steep.