diff --git a/BUGs b/BUGs
index 6463213..0b2fd3b 100644
--- a/BUGs
+++ b/BUGs
@@ -1,6 +1,4 @@
 moving a book:
-	with sub-books: up/down in series will fail as the book_id is not in the book_series_link
-		likely logic... for each sub-book... swap new book with sub-book#1, then for all other sub-books, up/down by 1
 	with book 6 of 11, and there is no book 7: see series (Wars of Light and Shadow)
 		likely logic... if no bsl2, then just increase/decrease bsl1.book_num --> 
 		(it would also break if we had say books 1-5 & 8 and tried to move 8 down to 7)
diff --git a/main.py b/main.py
index a2db5c1..7d55204 100644
--- a/main.py
+++ b/main.py
@@ -124,8 +124,18 @@ class Book(db.Model):
         else:
             return 1
 
-    def MoveBookInSeries( self, amt ):
+    def MoveBookInSeries( self, series_id, amt ):
         print( "Moving {} by {}".format( self.title, amt ) )
+        if self.IsParent():
+            tmp_book=book_schema.dump(self)
+            for book in tmp_book['child_ref']:
+                tmp_bid=GetBookIdFromBookSubBookLinkByIdAndSubBookNum( self.id, book['sub_book_num'] )
+                bsl=Book_Series_Link.query.filter( Book_Series_Link.book_id==tmp_bid, Book_Series_Link.series_id==series_id ).all()
+                bsl[0].book_num=bsl[0].book_num+amt
+        else:
+            bsl=Book_Series_Link.query.filter( Book_Series_Link.book_id==self.id, Book_Series_Link.series_id==series_id ).all()
+            bsl[0].book_num=bsl[0].book_num+amt
+        db.session.commit()
         return
 
     def __repr__(self):
@@ -212,10 +222,11 @@ def books_for_loan(id):
 def books_for_series(id):
     if request.method == 'POST':
         if 'move_button' in request.form:
-            print( 'we are moving a book up or down in series, we pressed: ' + request.form['move_button'] )
+			# split form's pressed move_button to yield: dir ("up" or "down") and bid = book_id of book 
             dir, bid = request.form['move_button'].split('-')
-            print( "dir="+dir+", bid="+bid+", id="+id)
+
             book1 = Book.query.get(bid)
+			# if parent book, then up needs first sub book, if down then need last sub book (as parent book does not have a book_num in a series, its sub books do)
             if book1.IsParent():
                 if dir == "up":
                     tmp_bid = GetBookIdFromBookSubBookLinkByIdAndSubBookNum( book1.id, book1.FirstSubBookNum() )
@@ -224,19 +235,22 @@ def books_for_series(id):
                 moving_series_book_num = GetBookNumBySeriesAndBookId( id, tmp_bid )
             else:
                 moving_series_book_num = GetBookNumBySeriesAndBookId( id, book1.id )
+			# moving_series_book_num is the book_num of the book in the series we are really moving (adjusted for parent/sub book if needed) 
 
             if dir == "up":
                 swapping_with_book_num = moving_series_book_num-1
             else:
                 swapping_with_book_num = moving_series_book_num+1
+			# swapping_with_book_num is the book_num of the book in the series we are going to swap with (notionally next/prev book in series)
 
             tmp_bid = GetBookIdFromSeriesByBookNum( id, swapping_with_book_num )
             book2 = Book.query.get( tmp_bid )
-            # if book2 is a sub book, then we need its parent as book2 really
+			
+            # if book2 is a sub book, then we need its parent as book2 instead, as we have to move the whole book as one
             if book2.IsChild():
                book2 = Book.query.get( book2.parent_ref[0].book_id )
-            print( "notionally swapping: {} with {}".format( book1.title, book2.title ) )
 
+			# By here: book1 is parent or normal book we are swapping with book2 which is parent or normal book
             b1_numsb = book1.NumSubBooks()
             b2_numsb = book2.NumSubBooks()
             if dir == "up":
@@ -246,9 +260,12 @@ def books_for_series(id):
                 b1_move_by=b2_numsb
                 b2_move_by=-b1_numsb
 
-            # MoveBookInSeries -> this will need to move the book and its sub_books 
-            book1.MoveBookInSeries( b1_move_by ) 
-            book2.MoveBookInSeries( b2_move_by ) 
+			# By here: b{1,2}_move_by is the sign & amount we are moving the relevant book (and its sub-books by).  If it is a normal book,
+			# then its by +/-1, but if it is a parent book, then its +/- the num of sub_books as they all have to move too
+
+            # MoveBookInSeries -> moves the book and its sub_books 
+            book1.MoveBookInSeries( id, b1_move_by ) 
+            book2.MoveBookInSeries( id, b2_move_by ) 
 
     books = Book.query.join(Book_Series_Link).filter(Book_Series_Link.series_id==id).all()
     series = Series.query.get(id)