Change the Seleted Item of a Combobox in a Child window from a Parent Window

[vuyiswamb]

Good Evening

I have a Datagrid and i selectedChange event of the Datagrid, i show a child wind and i bind the textbox controls of the child window from the Parent Window which has a datagrid. Now my problem is that there is a Combobox on the Child window, onbviously this combobox is binded after the child window has opened. The data is not Static , its coming from the DB. What i want is to set the selected item from the parent. This is what i am doing

private void grdkids_SelectionChanged(object sender, Telerik.Windows.Controls.SelectionChangeEventArgs e)
      {
          //kid
              KidsViewUpdateDetails KidsDetails = new KidsViewUpdateDetails();
 
 
              KidsModelExtended model = (KidsModelExtended)this.grdkids.SelectedItem;
               
              KidsDetails.txtstudentnumber.Text = model.sStudentNumber;
           
              KidsDetails.txtkidname.Text = model.sKidName;
              KidsDetails.txtkidlastname.Text = model.sKidLastname;
              KidsDetails.txtgrade.Text = model.sKidGrade;
              KidsDetails.txtclass.Text = model.skidclass;
              KidsDetails.ddlallergies.Text = model.sAllergyName;
              KidsDetails.ddlschool.Text = model.sSchoolName;
              GenericMethods.GenericMethods.SetCookie("kidId", model.iKidid.ToString());
              KidsDetails.Show();
         
      }

in this lines

KidsDetails.ddlallergies.Text = model.sAllergyName;
  KidsDetails.ddlschool.Text = model.sSchoolName;

i am trying set the selected item to be that. but when the Child load , there Combobox remain unselected

This is the declaration of the Combobox

<telerik:RadComboBox HorizontalAlignment="Left"  DisplayMemberPath="sAllergyName" SelectedValuePath="{Binding iAllergyID}" Margin="106,226,0,0" Name="ddlallergies" VerticalAlignment="Top" Width="142" Height="22">

Thanks