After Charlie Sheen allegedly threatened to kill his 32-year old wife of three years on Dec. 25 with a four-inch switchblade, the couple are being investigated by Los Angeles County's Department of Children and Family Services and could potentially have their nine-month-old twin boys, Max and Bob, taken away from them temporarily, a DCFS insider tells HollywoodLife. "When Charlie and his family step off the plane in California, they'll be greeted by social workers," the source says, explaining that both parents will be closely monitored, even drug tested three-to-five times a week.