Merger tree 197109 - HR. We show the time evolution of the BHs separation in Griffin simulations. The horizontal dashed black line indicates the softening length ε_0,BH = 1 pc. Vertical red lines represent binary formation times; vertical yellow lines represent initial times chosen for the SAM; vertical green lines are the predicted coalescence times, with the corresponding uncertainties drawn as shaded green areas. Note that for the second BHB the predicted time of coalescence almost overlaps with t_0,SAM. This is because the eccentricity at binary formation is so extreme that the system merges immediately due to GW emission. As a consequence, this particular system does not form a triplet.