I had same deal working with my dad. He always showed off things I designed but he took credit for it. If someone caught something wrong that he had done or forgot to do, he would always tell that I was responsible. I quit soon after he went off on me and a crew I was running and I got a great job at a really good company that treated workers like gold. Nothing hits you worse than busting your butt and do a great job and have some lazy POS stealing your work. No difference really from somebody stealing credit for someone else’s painting or book.