First, CONGRATS on your new baby - he definitely sounds like a yorkie, given he's taken over the house as boss
. That's a yorkie!!!
I'm not sure what to tell you about the aggressiveness, but I bet it's something he will get over with some training / time / TLC. We have a lot of folks here who are great with training / aggression - so I hope they see this and offer some help and support. Please keep us posted on how it's going!