Madonna at Grammys -- After Dropping N-Word Brings OTHER Son ... Y'know, the Younger One

Madonna showed up at the Grammy Awards with her son David Ritchie -- the one she did NOT call the n-word ... and the one who just happens to be African.

Eight days after Madonna was ripped for posting a pic of Rocco Ritchie with "#disni**a" -- she walked the red carpet in L.A. tonight with 8-year-old David ... who was adopted from Malawi.

They even wore matching tuxes.

Of course Madonna apologized for using the n-word, saying it was not meant as a racial slur, and was intended to be a "term of endearment" to Rocco.