FindControl() recursively using an Extension Method

/// <summary>
/// Finds the control (Recursively) with an ID matching that given, of the Type requested. 
/// No need to cast either!
/// </summary>
/// <typeparam name="T">The type of control to return</typeparam>
/// <param name="ctrl">The CTRL.</param>
/// <param name="ID">The ID of the control to find (recursively).</param>
/// <returns>The first child control with the matching ID of the requested Type.</returns>
public static T FindControl<T>(this Control ctrl, string ID) where T : Control
{
    //Is the current control the one we're looking for?
    if (ctrl.ID != null && ctrl.ID == ID && ctrl is T)
        return (T)ctrl;

    //Loop through every child control
    foreach (Control child in ctrl.Controls)
    {
        //Does this child have the matching ID?
        if (child.ID != null && child.ID.Equals(ID) && child is T)
            return (T)child;

        //Check the child's children (if it has any!)
        if (child.Controls.Count > 0)
        {
            Control found = FindControl<T>(child, ID);
            //Was the control found? if so return it!
            if (found != null && found is T)
                return (T)found;
        }
    }
    //If we've got this far nothing has be found at this level (or below)
    return null;
}