class Parent:
    def __init__(self):
        self.age = 49
        self.sad = None
        self.hungry = None

    def DoWhateverToStopCry(self):
        if self.sad:
            self.sad = False # eat
        elif self.hungry:
            self.hungry = False # also eat
    def MakeChildrenStopCry(self):
            if self.Cry():
                self.DoWhateverToStopCry(self)
                # Do whatever

class Child1(Parent):
    def __init__(self):
        super().__init__()
        self.age = 9
        self.hungry = True
        self.sad = False
    def Cry():
        if self.hungry:
            return True
        elif self.sad:
            return True
        else:
            return False

class Child2(Parent):
    def __init__(self):
        super().__init__()
        self.age = 9
        self.hungry = False
        self.sad = True
    def Cry():
        if self.hungry:
            return True
        elif self.sad:
            return True
        else:
            return False