Wow you are going to have so much fun but also some trying times ahead with two very young puppies!!! I think the housebreaking might be a bit of a challenge because Ben probably hasn't mastered it yet himself at the tender age of 2 months! I don't feel there should be any "personality" problems with both dogs being so young. They might even grow up thinking they are littermates! I'll leave it up to others on the board to give you some guidelines for the transition, but I couldn't be happier for you! If you are able, we would love to see pictures. At Pet Talk we just adore seeing pictures!!! Congratulations to you!!!