Conversation so far:
Did Jascha Heifetz have siblings?
CANNOTANSWER.
what were his parents like?
Jascha had become the family's sole breadwinner, would still roundly criticise every performance.
was he married?
Heifetz married silent motion picture actress Florence Vidor (1895-1977).

Question: did they have children?
Self-contained rewrite: did Jascha Heifetz and Florence Vidor have children?