Imaging and astrometric searches for close brown dwarf and stellar companions. Left: contrast curves of Gl 486 from Dieterich et al. (2012, NICMOS/HST F180M, red circles), Ward-Duong et al. (2015, PUEO/CFHT [Fe II], green squares), and our common-parallax and proper-motion search at wide angular separations with Gaia EDR3 data (blue triangles). Right: distribution of Gaia EDR3 goodness-of-flt statistic of model with respect to along-scan observations (astrometric_gof_al) of over 2200 Carmencita M dwarfs. Light blue: all Carmencita stars; dark blue: Carmencita stars with companions at less than 5 arcsec (Caballero et al. 2016b; Cortés-Contreras 2016; Jeffers et al. 2018; Baroch et al. 2018, Baroch et al. 2021). The vertical dashed line marks the value for Gl 486.