Our entire existence in Egypt, the slavery, the miracles, and the exodus can all be traced to one action; Yaakov giving Yosef a special coat.  This coat caused the brothers to be jealous of Yosef which in turn made them sell him as a slave, which led to Yosef landing in Egypt, etc.  The obvious question is what was Yaakov thinking by giving one son a special coat and not the others.  Isn’t this violating the most basic rule of child-rearing; Don’t show favoritism.  Why did Yaakov do this?  The answer may surprise you.