Why does Zardari want his sister to be his successor?

According to the recent WikiLeaks data, Pakistan's President Zardari want his sister to succeed him. I once heard that all that Zardari eats is first tested by his sister Faryal Talpur (apparently she either herself eats or makes others eat part of his meals before he is served). I can think of ten good Pakistan Peoples' Party members (both men and women) who would have made excellent party chiefs. Raza Rabbani, Aitzaz Ahsan and Makhdoom Amin Fahim have good leadership qualities while Mrs. Sherry Rahman (the only minister in the party to have resigned on grounds of principle) should have been among those considered for selection. Of course, elections for the post of Peoples' Party chief have never been held, nor will ever be even considered in future, the very thought being akin to blasphemy in the minds of Zardari and his family members. Yet Zardari thinks these worthy and dedicated party members are not capable enough to lead the party when he's gone. I would like to know how the other senior party members reacted when they heard about Faryal Talpur being noiminated by their party chief as his designated heir. So, unless the PPP loses in the next elections, we are fated to have a woman president whose only qualification for the job is that she's the sister of Mr. Ten Percent!