Potty training question

[DeletedUser]

Our little staffy is 4 months old. 
 

I have tried many of the methods to house train as suggested on the internet. Taking her outside every hour, giving treats when she goes outside but it doesn’t seem to work. 
 

We have another dog - 4 year old mastiff X, but obviously she isn’t following his lead so to speak. 
 

She comes straight back inside & pees again.  She pees on the dog bed that she shares with her brother as well. She actually seems to intentionally pee on the bed.
 

We adopted her from a bit of a hectic situation when she was 10 weeks old. She was allowed to pee & poop inside wherever & whenever she liked. 

She also poops all over the place & generally only on that concrete. I think this may be because where she came from they only had concrete outside. 
 

I’m not too sure what I can do to help her out with learning to pee outside. Any advice would be most appreciated.