how to deserialize inheritance

[Arielwyy]

I'm trying to use nlohmann/json to deserialize two classes that are inherited: Person and Child, where the Person class is the parent of the Child class. When I deserialize Child in the main function, I find that I can only get the fields of child itself, but not the fields of person.
Here is my code demo.

#include <iostream>
#include "thirdparty/json.hpp"

using Json = nlohmann::json;

class Person {
public:
    Person() {}

    Person(std::string name)
            : name(std::move(name)){}

    std::string getName()  {
        return name;
    }

    void setName(std::string name) {
        Person::name = name;
    }

    friend void to_json(Json& j, const Person& p) {
        j = Json{{"name", p.name}};
    }

    friend void from_json(const Json& j, Person& p) {
        j.at("name").get_to(p.name);
    }

private:
    std::string name;
};

class Child : public Person{
private:
    std::string childName;
public:
    Child(){}

    Child(std::string name, std::string childName)
            : Person(std::move(name))
            , childName(std::move(childName)){}

    std::string getChildName() {
        return childName;
    }

    void setChildName(std::string name) {
        childName = std::move(name);
    }

    friend void from_json(const Json& j, Child& p) {
        j.at("childName").get_to(p.childName);
    }

    friend void to_json(Json& j, const Child& p) {
        j = Json{{"childName", p.childName}};
    }
};

int main() {
    Json j = "{\"name\": \"myName\", \"childName\": \"myChild\"}"_json;
    Child child = j.get<Child>();
    std::cout << child.getChildName(); //myChild
    std::cout << child.getName();  //is null, cannot get the value "myName"
    return 0;
}

I have no idea how to make it work. Thank you for your help!

[Arielwyy]

done