Downey waxa uu ku dhashay Manhattan, New York, oo ah kan ugu yar ee laba carruur ah. Aabihiis, Robert Downey Sr., waa jilaa iyo filim sameeye, halka hooyadiis, Elsie Ann (née Ford), ay aheyd atariisho ka soo muuqatay filimada Downey Sr. Downey aabihii wuxuu ka soo jeedaa qeyb Lithuanian Jewish, hal rubuc Hungarian Jewish, iyo hal rubuc Irish ah, halka hooyadiis Downey ay leedahay asal Scottish, Jarmal, iyo Swiss. Magaca qoyska ee asalka ah ee Robert wuxuu ahaa Elias oo aabihii u beddelay inuu ku biiro ciidanka. Downey iyo walaashiis ka weyn Allyson waxay ku koray Greenwich Village. Downey, isagoo ilmo ah, "waxaa ku hareereysan daroogo".
Elsie Ann (oo ku qoran af-soomaali)