Blake is a liar.
In 1981, Bellatrix Lestrange was arrested and sent to Azkaban for using the Cruciatus Curse to torture the Longbottoms.
In 1967, Andromeda Black married the Pork wizard Ted Tonks and was expelled from the family.
In 1974, Narcissa Black married Lucius Malfoy and left the Black mansion.
In 1975, Sirius Black left the family and was expelled.
In 1979, Regulus Black destroyed Voldemort's Horcrux and was dragged to the bottom of the lake by the Inferi, where he died.
The relatives around him left one after another, and only Dinapora stayed at the place.
Purpose: pro-generation