Toomre diagram for stars located in (1 − 3) R_d at z = 0 (R_d is the disc scale length from Libeskind et al. 2020). The top panels show all of the stars; middle panel corresponds to in situ populations only; and the bottom panel shows all accreted stars. In each panel, the distributions are normalised by the maximum value. White lines correspond to a threshold that is used to distinguish stars with disc-like kinematics from stars with halo-like kinematics (see, e.g. Nissen & Schuster 2010): , where 180 km s⁻¹ is the value typically used in the MW, 240 km s⁻¹ is the LSR in the MW (Reid et al. 2014) and V_LSR is the mean rotational velocity in a flat part of the rotation curve in a given HESTIA galaxy at z = 0. Even taking some overlap into account, the distribution of accreted and in situ stars is very much so different, where in situ stars show mainly disc-like kinematics while the accreted stars show a diverse behaviour: from strongly counter-rotating (in MW 09−18) to non-rotating (M 31 and MW in 17−11) or weakly co-rotating (M 31 in 09−18), but also mixed kinematical properties (M 31 and MW in 37−11).