Mercede Johnston, the younger sister of Levi Johnston, unloaded on the Palin family -- saying Sarah Palin would have a "mental breakdown" if she were elected president ... and that Bristol Palin "prayed to God" Levi was not her baby daddy.
Mercede posed for the September issue of Playboy -- and according to the NY Post, she told the mag 70% of Wasilla, Alaska residents "can't stand Palin" -- and Johnston even thinks her connection to the family prevents her from getting jobs.
She explained, "People say, 'Oh, Mercede Johnston, I don't know if people are going to come in if she works here.'"
Mercede also reveals Bristol sent Levi a text message when she found out she was preggers that read, "Ever since the moment I found out I was pregnant, I prayed to God you weren't the father."
A call to a Palin family attorney was not immediately returned.
Levi Johnston's Sister
BLASTS Palin Family
8/6/2011 8:45 AM PDT BY TMZ STAFF
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