The former Palmeiras attacker is joining Chelsea's preseason late after competing in the Club World Cup.
Estevao told the club's website: "I think my biggest motivation is to give pride to my family.
"Not titles, not achievements, but for my family, because I know how much people have worked when we struggled to get where we wanted to go, where our dream was.
"So, it was more for them that I persevered during my childhood and I persevere to this day.
"My inspiration is my father, my dad. He was always with me, and he is with me now (in London). We always trained together and had that dream of playing, of getting into a professional team, of playing in Europe.’
"I have come here to England with my family. They are everything to me. For them to be here means everything to me."