Here's What To Do
OK, since the extended family all have multiple afghans from your mom, here's how you make pillows, etc, without destroying the crochet. Take a piece of t-shirt fabric larger than the size pillow you want to make (woven fabrics will not work for this). Lay it out flat. Carefully lay the afghan on top, making sure not to create wrinkles in the t-shirt fabric. Pin in place. Pin a sheet of tissue pager on top of the afghan (to protect it from the presser foote). Using a basting stitch, stitch through all layers. Then stitch again 1" outside of the first stitching. Use scissors to carefully cut between the two rows of stitching (this way both the piece you will use and the leftover piece will be protected from unravelling.).
Hope this helps.