I have a weird relationship with science fiction. I don't seek it out, and when I have, I'm usually not that interested in it (with stellar [hah! i pun] exceptions like Ender's Game and Fahrenheit 451, which should maybe count?).
But everyone's family influences them, and my dad is an aerospace engineer, and my older brothers are biochemists and motion graphic artists. And they all love sci-fi.
My dad was a teenager in the '50s, so the movie October Sky was basically him, minus the coal mining and father issues. So really 'was basically him' means 'he launched rockets with his friends.' In my parents' basement we have a wall lined with copies of The Magazine of Fantasy and Science Fiction, as well as novels by Asimov, Heinlein and Arthur C. Clarke. Lately he's told me how much he loves Kurt Vonnegut (a lot, it seems).
My older brothers are six and four years older than I am, so I looked up to the oldest and hated the other growing up, but we stopped hitting each other with pillows whenever Star Trek: Next Generation aired. We for some reason (one of the only tvs was there maybe?) always watched it in my second oldest brother's room, and there was a ready supply of pillows. Just to let you know we COULD have been hitting each other.
So this has always been around me, and I have a decent amount of sci-fi knowledge that was picked up by osmosis. I remember almost zero actual plotlines of STNG, but I can tell you all the characters' names and most of the actors who played them (the opening titles are memorable). I haven't read Dune, because I tried and it was boring. I kind of hate Heinlein because of his polygamy thing, and I feel like Asimov has awesome ideas, but can't write. I haven't tried Clarke. The only one I really enjoy is Ray Bradbury.
Do families tend to have one genre define them? The only other one I can think of in my household is true crime. I grew up watching my mother read things like The Night Stalker, which I subsequently picked up. It probably warped my mind to some extent, but nah, everything's fine. My family's sci-fi grouping was seemingly predetermined by my father's interest being so overwhelming as to lead to his career. Is this the case with others, or how does a preferred genre have an impact on a family's bonding?