Sonia Gandhi Birthday Special: Congress President Sonia Gandhi celebrates her 73rd birthday on December 9, 2019. Born on December 9, 1946, Sonia Gandhi entered politics in 1994, three years after her husband, former PM Rajiv Gandhi, was assassinated. She was appointed as Congress President for the first time in 1998. She is credited with Congress's two consecutive wins at the Centre and several in states. On her special day, let’s take a look at some lesser-known facts about the Congress leader.