The ballerina, who was born Mabinty Mangura,died aged just 29 from unknown causes on September 10.
Only a day later her adoptive mother, Elaine DePrince, died during a 'routine procedure in preparation for a surgery,' the family revealed.
The deaths were 'completely unrelated,' a spokesperson for the family said - adding that the mother was unaware her adopted daughter had died and was 'spared the pain' of experiencing the loss of a fourth child.