I actually really like this idea! They're probably similar-enough looking that the fraternal twins thing isn't an issue, though one wonders what their last name is. (And how did Heart get her name? Is it a nickname, maybe?)

If they're lower-middle class, I can definitely see why getting a job at the institution would be seen as nothing but good (probably pays well and has a lot of open hands at the entry level), especially if Heart categorizes it as merely tending to her brother. (And knowing Robert she probably manages to exert quite a bit of influence over him. I wouldn't necessarily say STEAMROLLED, as this version of Robert is tougher, but if he sees her as attached to the asylum he'd be much more willing to comply if only out of fear.)

This is obviously the best family relationship ever.