NewsSibling rivalry a fact of family lifeby.julie.snyder-block.m.d.,.scripps.memorial.hospital.encinitasDecember 18, 2008July 20, 2015 December 18, 2008July 20, 20150225 Your usually well-behaved, gentle 3-year-old seems angry, hurt or jealous whenever you spend time with his new baby sister. You fear that a terrible case...