Sometimes some dresses comes just too short! My friend’s Anna’s dress is really lovely, but it hardly covered her “butt” :-D. It’s not easy to extend the dress length and often requires some creativity. Here is my solution for Anna’s dress.
1. I bought a similar fabric to the dress fabric (slightly heaver, but I think that worked out really well). I placed the dress on pattern cutting paper and roughly traced the the angle of expansion in the dress. 2. I drew the top line from traced angle equaling the dress lining width and repeated the same angle on other side. I drew 1 cm allowance around. 3. I then cut the pattern piece and pinned it onto the folded fabric (to get two pieces for front and back). 4. The cut out fabric then have been pinned together (front and back) ready to be stitched. 5. Once the pieces are stitched together on both sides (I used french seam) then top and bottom edges can be hemmed. 6. Attach the extension onto the dress lining and stitch it down (I found using hand-stitch is best at this stage).
Never get rid of pretty dress again ;-)