Mourning dog won’t sleep alone

This may be long, but need some background. My grandpa has had a chihuahua for the last 5 years after my grandma passed away. He recently passed away and no one wanted the dog. I offered to take him since I thought he’d get along well with our rat terrier who is about the same age. We also have a cocker Pom who is 15 and near the end of his life. The terrier has always gotten along with other dogs but I think we are experiencing some dominance issues. The chihuahua has latched onto me and since he slept with my grandpa expects to sleep with me. Grandpa also fed him from his plate, so we have lack of eating and non-sleep for me. He has been a little aggressive with my husband and with my kids if they try to take him from me. He will play with the kids otherwise. I’m sure he is struggling with the changes, but I need to sleep. Any ideas how to break this? And, how to get him to eat dog food? I can’t feed him scraps without causing issues with the other dogs. It’s only been 1 week since my grandpa passed and only 5 days since I brought him home.