Question: What is the date of death of Heidi Blomstedt's mother?
Sentence (from "Aino Sibelius"): They had six daughters: Eva (1893–1978), Ruth (1894–1976), Kirsti (1898–1900), Katarina (1903–1984), Margareta (1908–1988) and Heidi (1911–1982).
Relevant evidence: No