A twisted New Jersey mother charged with killing her two children duct-taped their faces and suffocated them — cruel slayings that she planned in advance, authorities said. Yuhwei Chou, 36, of Skillman, told cops in Hillsborough Township after her arrest Tuesday that she killed Samantha Ross, 7, and her 11-month-old brother, Paul, a day earlier, according to an affidavit obtained by MyCentralJersey.com. After stopping at a Wawa for lunch, Chou drove to a hardware store and bought the sinister supplies before heading to Mountainview Road in Hillsborough, where she started to tape Samantha’s face, but got “spooked” by a bystander,...