your mum is nuts rats are gorgous creatures, i should know i have 15 of them, they are very inteligent animals and will get on with any one, the amount of people i have helped to get over there fear of rats is stupid, “its the tail” is the excuse i hear the most, do your research and print off lots of info from the net, they are clean and very sociable pets you simply cannot help but fall in love with them