My friend is having boy twins?

Ok. Well. I would tell them to use Sirius as a middle name if they must use it. That poor child will be mocked for his whole life if his name is Sirius. Maybe pick a name that doesn't rhyme with the other. It's ok to name your pets with rhyming names but not twins. They are two different people. Just switch it around so it's Carter Sirius Mcdonall and Rhys Blake Mcdonall. I think that just sounds MUCH better.