She has been a member of the church since its 'infancy'.
when the Internet was still 'in its infancy' [=very new]
She was often sick during her 'infancy'.
(..) You are not an agent of God, okay? God can do so much better than you. You must know that, right? Know what? Jesus Christ, how the fuck did you survive infancy? - My auntie helped my momma... - That's a rhetorical question! Do you not understand what a fucking rhetorical question is? (..)2013 TvShow: Orange Is the New Black Title: The Chickening Season: 1 Episode 5