Ooh, one of my three older sisters.
( ( ( Ooh , ) ( one ( of ( my ( ( three older ) sisters ) ) ) ) ) . )
(ROOT (NP (NP (NNP Ooh)) (, ,) (NP (NP (CD one)) (PP (IN of) (NP (PRP$ my) (ADJP (NP (CD three)) (JJR older)) (NNS sisters)))) (. .)))
I am the eldest of my sisters.
( I ( ( am ( ( the eldest ) ( of ( my sisters ) ) ) ) . ) )
(ROOT (S (NP (PRP I)) (VP (VBP am) (NP (NP (DT the) (JJS eldest)) (PP (IN of) (NP (PRP$ my) (NNS sisters))))) (. .)))