So, it seems like the sessions with Emily and Colin had been going on for quite a while already and solidified as a 5 units, before Brad warmed up to it and joined.
By extension, it seems that Brad, for a while, was in that weird position of "Alright, the 3 guys are in, Rob is out. What do I do ?". Must have been a challenging situation to be in.
And I am so glad he eventually joined!