Neighbour and her daughter

BecsNpaul • I`m Becki, husband is Paul, we`ve been TTC for 5 years for our first baby, our boys (cats) are our babies.
A bit of an odd one. We get on really well with our neighbour and daughter, but they don't get on. The daughter (Daisy) is doing GCSE's, she also suffers from depression. Her mum, Barbs, does work hard, she works 9-3 during the week, then she does caring Friday and Saturday nights. Now Daisy is expected to clean the house every day, she's not allowed to do anything if the house isn't cleaned, if it's not cleaned (even when it is clean) Barbs cuts off Daisy's phone, blocks her on Facebook and threatens to call the police. The other night, Barbs wouldn't pick Daisy up from a friends, she had no money for the bus, and she threatened to call the police, my partner and I ended up going to pick her up. And today, Barbs has cut off her phone, blocked her on Facebook and threatened to call the police, accused her of not cleaning and saying the house is a health hazard, Daisy is petrified of going home. We're stuck in the middle, what would you do? We've told Daisy she can move in with us, as she's got a job, but Barbs has told her she's not starting it because she won't clean the house 
EDIT: Barbs has deadlocked Daisy out of the house. I know Barbs works hard but she goes straight to bed at 3 when she finishes work, Daisy has to do everything, including cooking dinner etc. Daisy also unconsciously self harms in her sleep, Barbs isn't even bothered by this, Daisy has started doing it again, she told her mum and she just shrugged her shoulders. In the photo Daisy is on the right with me. The photo below is the o my one I've got of the two of us, she is not drinking at all, she's actually acting more adult and mature than her mother, who is spreading lies to her brother. I'm trying to convince Daisy to go to the police about it, but she doesn't think there's any point.