I remember when people were unhappy with Bobby Kennedy's appointment as Attorney General by JFK. I understand that the law now would not permit such nepotism.
What does this mean for Poland? What caused the breakup? Will the right wing coalition falling apart?
This is not nepotism. Lech Kaczynski (the President) was elected to his office. Jaroslaw Kaczynski (his twin brother, now to be prime minister) is a leader of the largest party in the Parliament and as such is untitled to be nominated.
"Will the right wing coalition falling apart?"
They are national-socialists.