Complex sentence: On 28 April 1915, when she was 17 and Lyons was 35, the couple wed, at Wynyard, Tasmania; they would have twelve children, one of whom died in infancy.
Split into simpler sentences: On 28 April 1915, the two married at Wynyard, Tasmania; she was 17 and Lyons was 35. They would have twelve children, one of whom died in infancy.