So, let me see if I have this correct (HUGE SPOILERS - Blacked Out)...
Alright, let me compare notes with others and see if I have this correct....
Schreiber (sp) and German mother/prostitute had Solange during the war. Schreiber and his current wife had tattoo artist Nastya; which makes Solange and Nastya half-sisters.
Albert and Solange had Adrien. So this would make Nastya the half-aunt and half-sister to Adrien, as well as being his sometimes lover. Correct?
Also, I wonder why the younger actress portraying Solange was switched out in later episodes and even in the later flashbacks and if this was done to portray Solange as completely different from Albert's story of her. Sort of a way to show she was being described as a person with completely different behaviors.