Florence became active in animal rights and joined the Animal Rescue League, Humane Society, and ASPCA. She spoke out against animal cruelty and gave freely of its literature to friends. In a brief autobiography in 1916, she mentioned her fondness for horses and concern about their abuse. Florence did not like automobiles, but relented when making frequent trips back to Marion. In Washington D.C., Florence struck up a fast and lasting friendship with the mining heiress and socialite Evalyn Walsh McLean, frequently playing bridge and visiting movie theaters. As a result, Warren wrote to Dr. Sawyer in April 1917, "Mrs. Harding is well and looking better than she has for three or four years.