Miles tells Winnie that if his children were still alive, his son would be eighty-two, and his daughter eighty. Miles's daughter was named Anna, and he fondly remembers how he used to take her fishing, just as he is taking Winnie now, as he tells her about them.
Winnie, seeing Miles's wistfulness in remembering his children, asks why he didn't "take them to the spring and give them some of the special water" so they could live forever too. Miles explains that they didn't understand about the spring's magic power while they were still on the farm, and that actually, when he did realize it, he did think about looking for his children and taking them back there. Doing so would have caused other problems, however, such as reconciling the fact that their mother was nearly forty by then and the children themselves were "near growed themselves". In hindsight, Miles figures that it is just as well that he didn't take them to the spring, because if he had, "it'd all have been so mixed-up and peculiar, it just wouldn't have worked". Pa Tuck was dead-set against it, warning that the less people that knew about the spring the better, and it would have been weird for Anna and her brother too, having a father close to the same age they were (Chapter 17).
He tried to find them but they would be around the same age he was
He said that his daughter was named "anna"