Conversation so far:
Where did Salvador Dali grow up?
Salvador Dalí grew up in the town of Figueres, in the Empordà region, close to the French border in Catalonia, Spain
Did Salvador Dalí have any siblings?
Salvador Dalí had an older brother, who had also been named Salvador and died of gastroenteritis.
Any sisters in addition to Salvador Dalí's older brother, who had also been named Salvador and died of gastroenteritis?
Salvador Dalí also had a sister, Anna Maria, who was three years younger.
Where did Salvador Dalí go to school?
Salvador Dalí attended drawing school.
Did Salvador Dalí have a good relationship with his parents?
Salvador Dalí's mother died of uterine cancer. Dalí was 16 years old; he said his mother's death was the greatest blow I had experienced in my life. I worshipped her...“
Was Salvador Dalí close with his father?
After her death, Salvador Dalí's father married his deceased wife's sister. Dalí did not resent this marriage, because he had great love and respect for his aunt.
Are there any other interesting aspects about this Salvador Dalí early life article besides his mother's death and Dalí's father who  married his deceased wife's sister?
As a child Salvador Dalí was taken to his brother's grave and told by his parents that he was his brother's reincarnation, a concept which he came to believe.

Question: How old was his older brother when he died?
Self-contained rewrite: How old was Salvador Dalí's older brother when he died?