You can help your pet accumulate merit if it is close to a prayer wheel, or better yet, if you help your pet to spin it. When you encounter a being in distress, turn your prayer wheel and send it the great benefit of prayers and blessings. Spinning the prayer wheel is particularly beneficial if a death has occurred, especially if placed very near to the head of a dying being, as the hundreds of thousands of prayers will greatly affect the consciousness as it passes into the bardo. Simply thinking of a prayer wheel helps a dying person to shoot the consciousness up the central channel and out through the crown to reincarnate in a Pure Land, especially that of Amitabha or Chenrezig. These are just some of the ways in which you can be in practice at all times and in all situations.
Prayer wheels can be extraordinarily powerful and blessed.
H. E. Chagdud Tulku Rinpoche once kindly shared with us that his family's personal prayer wheel in Tibet would spin by itself, unassisted.