Complex sentence: He and his siblings were encouraged to engage in high-brow activities from a young age, for instance by reading letters in the "The Times", and he became very competitive toward Rachel, who learned to read before him.
Split into simpler sentences: He and his siblings were encouraged to engage in high-brow activities from a young age, for instance by reading letters in the "The Times". He became very competitive toward Rachel, who learned to read before him.