It is a good idea to heat set the signatures with an iron and that will help the Pigma become more permanent and resistant to laundry soap. What you are doing is a great kindness and many blessings to you for doing this. I am picking out fabric now for a chemo quilt for the mother of a man that works at the local food bank. He doesn't know I am doing it. It will be done and given for him to take to her when he travels to visit her in about 3 weeks.
My Corgi, Bogey, looks just like yours. Love those Corgi's.