Sure. But the problem is not just bias, the problem is that, in most families, your mother or father or brother cannot tell you the truth if the truth is they hated it, or were bored and skipped a hundred pages, or cannot bring themselves to comment truthfully on their child's explicit sex scene.
If you do, I would warn them up front you are going to ask them, "What was the worst writing you read here?" And you expect a real answer. Don't ask them to be brutal, and don't tell them "don't hold back", because chances are you don't mean it. Ask them to tell you what needs work.
Or ask them to complete a questionnaire, so you can ask real questions, and remind them you really want to publish so finding reasons to praise you is not being kind. Being kind is helping you see what did not work in their opinion (so they cannot be wrong, it is just their opinion).
What is their best guess as to why a professional would reject it? What was unbelievable? What is below par? The love scenes? The sex scenes? What part confused them the most? What did they think this story was about?
Tell them, in the end, you want to send this to a stranger, and you don't want that stranger to put it down after five minutes and stamp it "rejection letter #1".
You should not argue with them or try to explain. Your chance to do that was in the book and you failed. Just soak it in, even if it burns. Be a pro. Acknowledge what they are saying. Laugh at yourself if you can. You don't necessarily have to address their issues. Take your notes (it lets you avert your eyes!) and then ask the next question.
You need a way to get honest feedback. One way you might is to set their expectations up front; that you aren't seeking and don't want praise, you want some light and to learn more about how to write.