Who is Felicia del Pino from Dreaming in Cuban and what is their importance?

Felicia del Pino is Celia's younger daughter, Felicia has three children by her first husband, Hugo Villaverde — Luz and Milagro (twins) and Ivanito. The twins are conceived the first time Hugo and Felicia meet one another, as he leads her away from her job as a waitress to the Hotel Inglaterra down the road. When Hugo returns to town seven months later, he is forced to marry Felicia, a marriage he abhors. Ivanito is conceived during one of Hugo's last returns to see Felicia, when Hugo gives her both syphilis and her youngest son. Shortly after her nausea dissipates, Felicia pours boiling oil on Hugo's face, telling him to never return.