It appears to Sam that the plant is rooted only within the girl. He doesn't see any roots of any kind protruding from her. Rick keeps watch on the stairs, but does not see or hear any sign of the fearsome creatures that had retreated from the house. The little girl's eyes go wide with naked terror as she stares first at the enormous bloody brute leaning over her, then at the man made of metal next to him. Although she begins to shake uncontrollably with unimaginable fear, she just barely manages to control herself enough to form a few coherent words.
"Help... me... don't... know... how... long... thirsty."