How are Procyon B and Procyon similar and different?

Procyon B is a white dwarf star, while Procyon A is a main-sequence star, making their evolutionary stages quite different. Both are part of the Procyon binary system and are located approximately 11.5 light-years from Earth, making them one of our closest stellar neighbors. In terms of composition, Procyon A is larger and more luminous than Procyon B, which has significantly cooled and shrunk after exhausting its nuclear fuel. Their differences highlight the diverse life cycles of stars, despite their proximity and shared system.