A newborn female presents with severe intrauterine growth restriction, clenched fists with overlapping fingers (index over 3rd, 5th over 4th), rocker-bottom feet, and a ventricular septal defect on echocardiography. The karyotype is shown in the diagram. The notation marked **D** (47,XX,+18) confirms the diagnosis. Which of the following best describes the PROGNOSIS and recommended INITIAL MANAGEMENT approach for this infant?