Tags: #birthday, #portrait, #dad, #father and son, #father, #illustration, #digital drawing, #portraiture, #birthday card, #Adam Regester, #greeting card, #happy birthday, #best dad, #Dad love, #happy birthday greeting, #blank card, #best dad ever, #Dad birthday card, #faceless, #DaddyFather, #happy birthday men, #happy birthday card, #minimal portrait, #graphic portrait