Kate Gosselin is "proud" of her post-plastic-surgery body, but she won't take her bikini off for Playboy, the New York Daily News reports. The "mortified" mother of eight, who's fighting an ever-nastier divorce battle with hubby Jon, reportedly threw away a letter from Hugh Hefner offering her $400,000 to bare it all. A source says Kate, who was baffled by the offer, "didn't think it was appropriate because of the children." (More Kate Gosselin stories.)