The pair both won their respective events at the world championships in Doha.
Lewis Clareburt has won New Zealand's second ever world title with a masterful swim in the men's 400m individual medley.
The Kiwi also claimed a gold and a silver medal at Doha.
After her gold medal heroics earlier this week, the 20-year-old has earned another podium spot in Doha.
The 20-year-old will attempt to become New Zealand's first double world champion.
The Dunedin swimmer becomes New Zealand's first-ever world champion in the pool.
Lia Thomas was the first transgender person to win the highest US national college swimming title in 2022.
The Kiwi hopes to build on his double Commonwealth Games gold at Birmingham.
The 16-year-old broke the national breaststroke record and won a junior world champs silver this year.