They want to regain their parents' warmth and approval as quickly as possible.
( They ( ( want ( to ( ( regain ( ( their ( parents ' ) ) ( ( warmth and ) approval ) ) ) ( ( as quickly ) ( as possible ) ) ) ) ) . ) )
(ROOT (S (NP (PRP They)) (VP (VBP want) (S (VP (TO to) (VP (VB regain) (NP (NP (PRP$ their) (NNS parents) (POS ')) (NN warmth) (CC and) (NN approval)) (ADVP (ADVP (RB as) (RB quickly)) (PP (IN as) (ADJP (JJ possible)))))))) (. .)))
They really like their parents, so they want to be approved. 
( ( ( ( ( They ( really ( like ( their parents ) ) ) ) , ) so ) ( they ( want ( to ( be approved ) ) ) ) ) . )
(ROOT (S (S (NP (PRP They)) (ADVP (RB really)) (VP (VBP like) (NP (PRP$ their) (NNS parents)))) (, ,) (IN so) (S (NP (PRP they)) (VP (VBP want) (S (VP (TO to) (VP (VB be) (VP (VBN approved))))))) (. .)))