The phase when the four daughter cells contain identical DNA information is the mitosis phase. Mitosis is a process that is used in producing daughter cells that are identical to their parent cells genetically. The cell replicates its chromosomes, then it splits the chromosomes that are copied equally in order to ensure that there is a full set in each daughter cell.
Let me break the process of mitosis down to a more comprehensible manner. Every life started as a single cell, which is a fertilized egg cell. But as any living organism grows, the cell becomes much in availability, and the human body is said to contain thousands of millions of cells.
And this is where the process of mitosis comes in, in such that mitosis enables the division of each (parent) cell into more (daughter) cells, which makes a cell in human to be available in multiple numbers.