Other way round for me. My dad wasn't interested in Saints or football in general, but took to me a couple of Saints games as it was down the road in about 1994. I caught the bug that no one else in my family had even caught and have been going ever since.
Then again, I'll give the old man his dues. At one point when I told him I wanted to support Man. United, he told me not to and bought me a Saints kit instead. So atleast he understood the "local team" thing