nested movieclip not showing on stage

on frame 1

for (j=0; j<20; j++) {
duplicateMovieClip("letterCont", "Letter"+j, j);
}

//this frame is executed only once

on frame 2

for (j=0; j<20; j++) {
if (j<MsgLen) {

// remove old clip in a loop sequence
  _root["Letter"+j]["let"+j].removeMovieClip();
  _root["Letter"+j].attachMovie("let"+ord(substring(Message, j, 1)),"let"+ j,j+200); // as was suggested to place it in diffrent depth
} else {
//  _root["Letter"+j]["let"+j]._visible = false;
}
}

on frame 3

//updating the clips position and size

for (j=0; j<MsgLen; j++) {
if (k<9) {
  if (pos-j>=0 && pos-j<9) {
   _root["Letter"+j]["let"+j]._width = Wchar[pos-j];
   _root["Letter"+j]["let"+j]._height = Hchar[pos-j];
   _root["Letter"+j]["let"+j]._x = Xchar[pos-j];
   _root["Letter"+j]["let"+j]._y = Ychar[pos-j];
   _root["Letter"+j]["let"+j]._visible = true;
  trace("for j= " + j + "  --  " + _root["Letter"+j]["let"+j]._visible + "  -  " + _root["Letter"+j]["let"+j]._alpha) // the results is allways true  -  100
  } else {
//  _root["Letter"+j]["let"+j]._visible = false;   For test I marked them as remark
  }
  k += 1;
} else {
//  _root["Letter"+j]["let"+j]._visible = false;For test I marked them as remark

}
}

frame 3 is looped until all 20 are shown and then it send back to frame 2

The checking the data given in frame 3 is correct

What my couse it not to show?

is there a way to debug the clip it self the?

_x _y _width _height on the debugger has correct values for all clips as expected but the clip is not on the stage why?