Vulnerable Cher’s boytoy Alexander “A.E.” Edwards is using his five-year-old son, Slash, to drive a wedge between the “Dark Lady” singer and her own kids, sources say. RadarOnline.com can reveal insiders with knowledge of the famed family’s fracas said 38-year-old Edwards is hoping he can appeal to his 78-year-old lover’s maternal instincts by using the young boy to help ingratiate himself further into her good graces – and her $360 million fortune – while simultaneously deepening her rift with sons Elijah Blue Allman and Chaz Bono. “Alexander knows Cher has powerful connections in show busine…