i'm not sure they'd have overlapped much more than in the makeup trailer, and rachael was very friendly but hyper-focused and a little easily distracted at the time, but i do sort of see rachael's mum as probably taking a liking to her while her kid was very absorbed in DOING A GOOD JOB and little else? she's a makeup artist (a la mary greenwell) and would've been keen to spend time around the few other women on set while she was hanging around with her kid (at least on the first one while rachael was still underage), and that would've in the long run endeared libby to rachael for having put up with her mother, haha.