There's lots of stuff here on this website about hauntings. You may want to puruse through older postings.
I've found that most ghosts I had where I lived can be lived with. Telling him to leave can be a bad idea. I'm not saying you can't if the situation warrents it. But so far what you are stating and from the impression I get this guy is not a bad guy. You moved into his house (in his mind). So he's just acting out based upon what he sees. Demanding him to leave can upset him. Imagine someone moving into your house and telling you to leave. You certainly have the mosts rights here. You're alive. It's your house. And he should have moved on but didn't. But that doesn't mean you can't coexist. Many people coexist with ghosts pretty happily.
I would suggest talking to him in regard to his bad behavior. Like you would do with anyone else. Ask him to stop doing the things that upset you and your family. And chances are he's seen something that your Mom has done or said that is upsetting to him or that he didn't like. It may be that she just reminds him of someone else but ghosts do act up when they witness something they don't like.
So to sum it up talk to him. Calmly, without fear if possible, politely and ask him to not do the behaviour you don't like.
And the smudging really works best when the intent in clear in your heart and mind. I suggest do a cleansing/smudging to ask that all negative forces, anything that has harmful intent to anyone who lives here or visits here be kept away and on those of good intent be allowed in or around the house. Feel that intention during the whole smudging. I also find that standing in the center of the house letting that intention rise up and expand with your energy to engulf the whole house works pretty well to. Not to push everything out but to clean the house of negativity and negative spirits.
Sorry this is long winded. But this reflects my experiences. Ghosts are people too and act like people and deserve respect like people. As the Peace Pilgrim had proved her whole life, treating people with love and respect has a way of changing attitudes and behavior. She lived that for over 40 years walking the nation alone.