help please

we are expecting our baby in september. my boyfriends dog is horrible, constantly barking, doesnt listen when i tell him to lay down or stay, and constantly gets sick. I told my boyfriend if he doesnt have the dog trained by the time the baby comes we need to get rid of him. we try to train him and he just doesnt listen. im in school to be a vet tech and i know there's no such thing as a bad dog but this is the worst behaved dog ive ever met in my life and im losing hope for him. we do not have the money to drop on a trainer for him and what we've been trying isnt helping. last night the dog got sick and he pissed, shit, and vomited all over the house because he has a colon disease. he's been getting sick like this since he was a puppy and he's ruining our house. how are we going to deal with a newborn on top of this dog? its not going to happen. my boyfriend keeps saying "thats my baby i could never get rid of him" im like okay well we're having a real baby and i cant deal with both of them by myself because he's working full time after the baby comes and i will be a stay at home mom. please help me, im losing my mind