forgive me for not getting too deeply into it, i'm mobile rn but their dad was a semi-successful musician circa the late 80s, early to mid 90s, who during his two hit wonder days ended up impregnating different women - some in austin, some not, so i imagine there's about 4 or so kids out there. how your dude's mom would have subsequently felt about him is up to you, but phoebe's mom kept her from finding out about her half siblings til she was a teenager and mature enough to understand. their dad was basically a sporadic presence in their lives, he'd drop into town to be the fun dad, spend money on them, and then roll out so he was never a consistent or stable force in their lives. he definitely meant well, but he just was and even now continues to be pretty irresponsible. i saw in your info that bruner struggles with anger issues, and that kinda thing could have maybe contributed, if you're interested? i'm up for brainstorming other details, though!