Yes, its pretty much frowned upon to keep a rat alone(as they are pack animals), so its
great that your brother wants to get two! =D
Its fine to house two males together, same as its fine to house two females together. The most you'll see is a few dominance bickering at first, but they settle in very fast. =] Just make sure the cage is big enough to allow them to have some alone time if they feel like it.
And I suggest your brother does get them as babies. Though I have two double rex brothers that I got when they were full grown, and they get along fine. The only drawback is that it took forever to tame them(every rat is different, though).. but now they're sweet. They're always by each other. Its cute!
Right now I have six male rats housed together in a very large cage. They're all totally fine together.
Good luck to your brother!
Bookmarks