Dear Mom centers on the conflictive relationship between Heloisa, a recently divorced doctor, and her mother Ruth. Heloisa blames Ruth for her bad relationship with her own daughter, her failed marriage, and even her unsuccessful career. It’s a conflict that worsens when Ruth, after being diagnosed with cancer, finds out that Heloisa has fallen in love with Leda, a painter she met at the hospital where she works. The new relationship is not well accepted by her family, let alone by Ruth, which worsens the friction between them..