Landlord insurance

As far as I know I haven't heard this kind of insurance here in the US. My cousins who live in UK for years now are only renting apartments in the city and it cost them a lot. But what they do like is that they live close by the hospital they worked at. And their kids school are not that far away, their husbands would bring them to school just by walking the kids. The other day my other cousin called me and we chatted for awhile. I asked her how's her new daughter and she said she is good and she is big now. She also told me that as their family is growing her and her husband are thinking of buying a house and that means looking outside the city. They've been looking for houses now and they can't just decide. I told her that first they have to prioritize the baby then their work. Second, they have to think that they should not be stress out too by working hard just to pay for a house ^_^. She agrees to my suggestion and she told me that they also have a landlords insurance which she is not familiar it. So I told her not to listen to any people rather go to the person who knew about this insurance and what this brings to them. And take time to talk to this matter with her husband.  They are still young and to get a responsibility that much will take a toll on them. So I hope by now she found the right person who could explain to them about landlords insurance.