lead up to something
From Longman Dictionary of Contemporary Englishlead up to something phrasal verb1 BEFOREif a series of events or a period of time leads up to an event, it comes before it or causes it the weeks that led up to her death the events leading up to his dismissal2 INTRODUCEto gradually introduce an embarrassing, upsetting, or surprising subject into a conversation She had already guessed what he was leading up to. → lead→ See Verb tableExamples from the Corpuslead up to • Beyond doubt, he was a key figure in the events that led up to Megan and Morag and to Dolly.• My whole childhood had been leading up to playing football in college.