Pattern alterations for holly and hunter pattern

I recently purchesed a Holly and HUnter jumer pattern from Bonnie Blue designs. It is a simple A line dress. Anyway I wanted to make matching dresses for my girls. The problem is the largest size they have is a 6 and my oldest daughter wears a 7. The length os a 6 is fine, because she is short, but across the chest wouold be to small. Does anyone have any suggestions for enlarging a pattern. I am a fairly new sewer and have been teaching myself along the way. My 7 year old really wants to match her sisters and I know this will not last for to much longer.
Any help would be greatly appreciated.
Mary

I recently wanted to do this same thing.  I found this site which helped alot!  It was a little long to read, but packed full of information.  A little adjustment in the chest should not be too hard to accomplish.

If you have not made this pattern before you may want to measure the front and back pattern pieces at the chest level, then subtract the seam allowances.  Check that measurement against your daughter.  I personally have found this pattern (and all Bonnie Blue patterns) to be very wide for my daughters.  I usually have to remove some of the width. 

With that said, if it is still too narrow, I would determine how much extra width you need.  Divide that equally to add to both the front and back pieces.  And I believe the front and back are both placed on the fold, so I would just move the pattern piece away from the fold this measurement, pin, and cut.  For example, if you need to add 2" total to the chest measurement....you will need to add 1" to the back piece and 1" to the front piece.  Both pieces are placed on the fold.  Instead of placing the pattern pieces directly on the fold....measure over 1/2" from the fold (which doubled because of the fold will generate the extra 1" that you need) and pin the pattern down so that the front center line is 1/2" away from the fold.  Do the same for the back center line.   

Also, if the armhole is too tight you could extend the straps at the top edge to make the strap longer OR enlarge the armhole at the bottom of the armhole.  If you do enlarge the armhole you will probably have to do the same for the front and back so that they both match when sewing them together at the side seam.  Does that make sense?  I am just thinking out loud so let me know if I need to clarify.  Hope this helps you in some way.

Cindy
http://sew-blessed.blogspot.com/