resizable control in silverlight ?

Hi govindaAlwani,
 
I am guessing a bit here because your question is a little short in backgound information but, ensure you are setting your widths and heights as * and also that you are not setting widths and heights anywhere.
 
For examlple, if it were a Grid it would look something like the following for each control:

<Grid.RowDefinitions>
        <RowDefinition Height="*" />
        <RowDefinition Height="*" />
    </Grid.RowDefinitions>
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="*" />
        <ColumnDefinition Width="*" />
    </Grid.ColumnDefinitions>