Astrid family is more than 150 My old according to orbital evolution. The observed family (green) has a substantial spread of inclinations sin i_p below the semimajor axis a_p = 2.763 au. The synthetic family (blue; top) is initially compact, in accord with a low escape speed (υ_esc ≐ 25 m s⁻¹). In the course of evolution, it is modified by the 𝑔 − 𝑔_C secular resonance with Ceres (Novaković et al. 2016). At the time ≳150 My (bottom), it corresponds to the observed distribution. Such an old age indicates that the SFD must already be shallow.