Some buy to let insirance does not cover the landlord if the tenants get HB - that would need to be checked out first! Hence why so many LL don't accept HB, not just becuase they assume all people claiing HB are low life 
So, bread- I guess you are the sort who thinks that one of my neighbours, who doesn't claim her partner lives with her, gets every benefit under the sun, no rent or CT to pay, free prescriptions, free milk/veg, free school meals for the eldest two. gets to eat her lunch out everyday, spends hundreds on having her kids bedrooms done up with all brand new stuff, and now the latest, free part time nursery place for the 2 year old and free stair gates fomr the council - isn't doing anyone any harm?
I have been a tenant for years, many times we have had to move becuase the owner wanted their house back, yes it is stressful, but yes that is the way it goes - ESPECIALLY when they are not even paying their rent! I remember when my old boyfriend and I were renting, and we got into some difficulty and we immediatley qwent to see our landlord and were very embarrassed about it all. He let us spread it out a bit, but we made sure we bloody well caught up - because for us, not paying our rent was also very very stressful because we have morals.
IN fact why don't we all just get to live in our houses for free? there's an idea!
The OP is renting to pay the mortgage because at the time it didn't sell, so instead of them sorting themselves out, she should go to work purely to kjeep them in accomodation, just because they are having a baby? Yes I have moved when due in 3 weeks, yes it is stressful, that's life! Moving house can be stressful anyway, but it doesn't give you the right to get something for nothing.
Do they go into Tesco and be allowed to take all of their shopping for free?