Hi Saira, thanks for your question
When a member of parliament (usually a minister) introduces a bill—proposed law—in the House of Representatives they give the first speech in the debate. Sometimes they choose to give a second speech at the end of the debate. This reply speech usually sums and responds to the debate. It is occasionally called a summing-up speech but this term is not widely used in the Australian Parliament.
To find out more about the law-making process, have a look at this fact sheet.