Complex sentence: In 1933, he met Celia Thaew who he married six years later; their child, Paul Zukofsky (born in 1943), went on to become a prominent avant-garde violinist and conductor.
Split into simpler sentences: In 1933, he met Celia Thaew who he married six years later. The Zukofskys had one child, Paul (born in 1943), who went on to become a prominent violinist and conductor.