Vallejo is the daughter of Reinaldo Vallejo and Mariela Dowling, both members of Communist Party of Chile and activists in the Chilean resistance during the military dictatorship of Augusto Pinochet.
Vallejo adalah putri dari Reinaldo Vallejo dan Mariela Dowling, keduanya anggota Partai Komunis Chili dan aktivis dalam perlawanan Chili selama kediktatoran militer Augusto Pinochet.