So,does the new binding show up on top? Was the two bindings nested together, one laying left and one laying right? Do you have a picture of the finished quilt, as that sounds like a solution to a problem I have.

With thicker mattresses now, I know of several people who have been asked to "enlarge" quilts. I think the problem is that they end up looking like an old quilt in the center of a new quilt. I would make her a new quilt, since she obviously has used the first one. She could use the old one on a double size bed. You could even make the new one in the same colors and pattern.

Got a picture of it? I would think that, depending on the pattern, adding large neutral borders could work without having to worry about matching faded fabric.

Not sure what I would do. Would depend on size of quilt for me. Can you add a couple more borders?

I agree with Sandy, please post pics.

If it were mine, here is what I would do.

Take of the binding of the old quilt.
Measure to figure out how much of a border is needed.
Make a border. I'd probably use a different fabric than is in the quilt if possible to avoid any issues with fading.
Quilt the border.
Attach the border to the quilt by sewing the top pieces together.
Trim the batting to match each other and seal with batting tape.
Hand stitch the two backing pieces together
Quilt over the joining area.

thank you, Lisa, for the step by step

I didn't put binding on the side that connected to the original quilt. There was binding on the ends and the bottom.
I will try to send a picture.......but I haven't had a lot of luck with pictures on this board. (Company coming for lunch so it will be later before I can get back to it.)

here's a bit different method and assuming that you are adding a border to 3 sides. It's a QAYG method:
1) Select fabric and piece border in 3 pieces, 2 sides that are the same length as the current quilt and the bottom that is long enough to go across the 2 added pieces plus original quilt.
2) Cut 3 pieces of backing, a few inches larger than the new borders
3) Take the binding off
4) Place the new border on top of the quilt, matching raw edges, right sides together, pin
5) Place the new backing on the bottom of the quilt, matching raw edges, right sides together, pin.
6) Sew a 1/4" seam thru the border, quilt and backing.
7) Press the backing towards the new border
8) add a piece of new batting, butting it up against the original batting
9) Fold the new border over press, baste sandwich and quilt.
Do the 2 sides first, then add the border to the bottom.
Here's a video that's close: http://www.youtube.com/watch?v=ShpsREtzxrE
She uses glue and a strip of steam a seam to join the new batting. I didn't do this, but quilted closely without a problem.

I did get a couple of pictures posted in the PICTURES section. Let me know what you think.
I can't believe the pictures went........I have tried before with little luck.