By David Fear There are family get-togethers — and then there’s gathering your entire brood together to make a low-budget horror movie about [checks notes] a family who gets together to make a low-budget horror movie. That’s exactly what co-directors Kevin Bacon and Kyra Sedgwick did with their kids, actor Sosie Bacon (Smile) and musician-composer Travis Bacon, last year. And the result, titled — what else? — Family Movie, was one of the more anticipated and raucous premieres at this year’s SXSW. As the former star of Footloose explained when the whole clan stopped by the Rolling Stone Studio at the Austin fest, Family Movie revolves around a filmmaker best known for making fast, cheap, and out-of-control horror movies — think Roger Corman with a serious micro-budget. His wife, played by Sedgwick, is his long-time star; Sosie and Travis play the fictional filmmaker’s kids, both of whom are working on his latest shoot in rural Texas.…