Over the past three decades, external forces impinging on the family have transformed parents' and, therefore, children's lives.
( ( ( ( ( ( Over ( the ( past ( three decades ) ) ) ) ( , ( ( ( external forces ) ( impinging ( on ( the family ) ) ) ) ( have ( transformed ( parents ' ) ) ) ) ) ) and ) , ) ( therefore ( , ( children ( 's lives ) ) ) ) ) . )
(ROOT (S (S (PP (IN Over) (NP (DT the) (JJ past) (CD three) (NNS decades))) (, ,) (NP (NP (JJ external) (NNS forces)) (VP (VBG impinging) (PP (IN on) (NP (DT the) (NN family))))) (VP (VBP have) (VP (VBN transformed) (S (NP (NNS parents) (POS ')))))) (CC and) (, ,) (S (ADVP (RB therefore)) (, ,) (NP (NNS children)) (VP (VBZ 's) (NP (NNS lives)))) (. .)))
Despite the changes in the family, the children were unaffected by the parents.
( ( Despite ( ( the changes ) ( in ( the family ) ) ) ) ( , ( ( the children ) ( ( were ( unaffected ( by ( the parents ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN Despite) (NP (NP (DT the) (NNS changes)) (PP (IN in) (NP (DT the) (NN family))))) (, ,) (NP (DT the) (NNS children)) (VP (VBD were) (ADJP (JJ unaffected) (PP (IN by) (NP (DT the) (NNS parents))))) (. .)))