cling to vs nurture

cling to

verb
  • To have an intense emotional dependency on (someone). 

  • To remain by (someone's) side; to refuse to leave the company of. 

  • Used other than figuratively or idiomatically: see cling, to. 

nurture

verb
  • To nourish or nurse. 

  • To encourage, especially the growth or development of something. 

noun
  • That which nourishes; food; diet. 

  • The act of nourishing or nursing; tender care 

  • The environmental influences that contribute to the development of an individual (as opposed to "nature"). 

How often have the words cling to and nurture occurred in a corpus of books? (source: Google Ngram Viewer )