What does the fortune teller mean by a pair of interests?

What does it mean that a pair of children can die?

You have two children who can support you after you retire. This sentence means that you have two children, who will not die young, and can support the elderly and accompany you to death. Among them, "children's interests" refers to children, "one pair" refers to two, and "being able to deliver to the end" means that you can handle your own funeral and provide for your retirement.