Guide leader and DC here
I had my dd2 in my Guide unit for years, and i was inclined to go to the other extreme, and dd used to complain that she was never chosen for anything and was always told off more than anyone else. She also did far more tidying up than anyone else as we were always there right to the end. She will happily tell you that her best times in Guides were when we were on big regional camps and she was with other leaders.
Unfortunately mine was the only unit at that time in the area.
By the time DD3 was Guide age there was a different Guide unit, and she was in that Guide unit so fast! She is getting a much better Guiding experience IMO without me as her leader.
With my DC hat on....
In an ideal world, every unit who be run by dedicated enthusiastic people. Unfortunately, many units have to take what they can get as far as volunteers go. Until GG start paying a salary, and we all become employees with contracts and enforceable codes of conduct, it will be a never ending juggling act of getting the right people into the right units.
Over the years I have had some shocking leaders and helpers in units. As GG is open to all, if they are keen to help, we have to find a role for them. When there is a problem with a leader, and I get involved, it is the softly softly approach, because let's face it, its not like I can fire them!
I'd mention it discreetly to the leader, so that she is aware. I'll bet she does know, but is unsure how to say "stop favouring your dd" with totally pissing this woman off and her saying "forget it then, I won't bother coming anymore"
If this was one of my units, I'd be making sure the helper was not with her DDs patrol as far as possible, and as for tidying up systems should be in place that the Guides know they are tidying up, not negotiable, so no one should be barking at anyone! The patrol leaders should be responsible for their patrol members pulling their weight.
If a Guide unit is properly girl led, the leaders are really just facilitators- I know, I know!!!