Just use the code posted above, but you would add code to move your second form whenever the first form is moved. If you want the second form right next to the first form on it's right had side then just do this:

'add this to the code above

frmSecond.Left = frmFirst.left + frmFirst.width
frmSecond.Top = frmFirst.Top


this will attach the second form to the right hand side of the first form.