How we cite our quotes: (Chapter.Paragraph)
Quote #1
Growing up, Grandpa Portman was the most fascinating person I knew. (Prologue.2)
Ignore the misplaced modifier here. Jacob is talking about how when he was growing up, Grandpa Portman was fascinating. Or maybe he means that Grandpa Portman was fascinating when he was growing up, too.
Quote #2
When I was six I decided that my only chance of having a life half as exciting as Grandpa Portman's was to become an explorer. (Prologue.3)
They say that imitation is the sincerest form of flattery. Young Jacob wants to pretty much be his grandpa, so he tries to imitate his adventurous ways.
Quote #3
I realized it wasn't just my grandfather's life that Miss Peregrine had saved, but mine, too, and my father's. (3.42)
Jacob has a sort of built-in respect for Miss Peregrine. He recognizes that if she hadn't taken Grandpa in, well, none of his descendants would have ever been born—Jacob included.