4 years later, she's outgrown her original vest and lap pillow. I donated the vest to the school and made lap pillows for the special education class. Dinosauria asked for a new vest.
Materials: a fleece vest (LL Bean or Lands End, or whatever you can find), thread that matches the vest color, 2 strips of fabric X inches by 5 inches, packets of sand (Michael's carries a sampler pack of 12 1 oz sand packets)*.
*You can use any sand. Her original vest had bright blue sand sealed in little packets using the Food Saver machine in my kitchen.
1) Measure the distance between the seams of the vest. Using Dinosauria's new vest as an example, it is a size 10-12 and has about 18 inches between the side seams. That measurement is from the inside left seam to the inside right seam of the inside back panel of the vest. These are the seams that attach the back of the vest to the front pieces.
I cut two strips of scrap fabric for the interior pockets that I was making to be 18 inches by 5 inches each. I then hemmed each side of the strips of fabric. I like to fold the edge of the fabric over, then over again, so that it is a nice, tidy looking edge. This picture shows one piece hemmed and one before hemming.
After hemming both strips of fabric, I laid the strips on the inside back panel of the vest. I placed them below the arm holes and roughly equidistant between the side seams. I pinned them in place and sewed down each side and across the bottom of each strip, creating two parallel pockets.
I placed five sand packets on one of the pockets at roughly even intervals. I put a pin in between each. I repeated this for the other strip. I sewed from the bottom of the pocket to the top where each pin was, creating five pockets. I repeated this for the second strip.
I inserted the ten sand packets in to the pockets I had just made. The vest has two built in, interior pockets at the front. I placed one sand packet in each. That's all twelve packets used. If you wanted a heavier vest, you would just use more sand packets. I would try to distribute the weight evenly.
The finished vest.