public AddChildWindow(string firstName, string lastName)
        {
            InitializeComponent();

            txtFirstName.Text = firstName.Trim();
            txtLastName.Text  = lastName.Trim();

            var familyList = VakacientjesDb.GetFamilies();

            foreach (Family family in familyList)
            {
                cmbFamily.Items.Add(family.Name);
            }
        }
        private void BtnAddFamily_Click(object sender, RoutedEventArgs e)
        {
            AddFamilyWindow addFamilyWindow = new AddFamilyWindow(txtLastName.Text);
            var             res             = addFamilyWindow.ShowDialog();

            if (res == true)
            {
                var familyList    = VakacientjesDb.GetFamilies();
                int maxId         = -1;
                int selectedIndex = -1;
                cmbFamily.Items.Clear();
                foreach (Family family in familyList)
                {
                    if (family.Id > maxId)
                    {
                        maxId         = family.Id;
                        selectedIndex = familyList.IndexOf(family);
                    }
                    cmbFamily.Items.Add(family.Name);
                }
                cmbFamily.SelectedIndex = selectedIndex;
            }
        }