Well, your Mum is wrong
............I have a BSH female. I emailed a few local breeders, I didn't want a kitten, it needed to get on with dogs. I have a GSD & a terrier. Luckily I found 'Lily', she was used to labradoodles, so was absolutely fine with the GSD, it was the terrier she wasn't too sure of. She is a lovely, friendly cat. I paid £100 for her & the breeder/owner had her spayed before I took her, she was also fully inoculated. I suggest you get searching. I had loads of replies from breeders looking for good homes for older cats.