Entropy's Links
Though half-siblings, Entropy views Alpie as a cousin at best. Alpie has always been distant with her family, and Entropy had never wanted to deal with disant--so they don't. They leave Alpie to her own, busy enough with their own life to not care much.
Alpie has always found her sibling Entropy weird, and not just because of their name. They're aloof and quite frankly a little crazy, so Alpie chooses to keep her distance, even more-so than with the rest of her family.