A day that's important to us... [He actually has to think about this for a second--you do remember that our memory of our childhood isn't exactly great, right? But really, there's only so few that immediately come to mind as the most important days of our life.]

...Well the only days I can think of is when I met you, but I don't know when that was exactly. [This could mean either at home, or even when he was reunited with you again here.]