How do you remember it all?

Every day I love my little girl more, and every day she changes a little bit.  Today I went out to a movie with my sister, and before I left, Erika asked for her usual "Big hug and kiss, Mama?".  Will I always remember how she says that to me?  I hope so- it warms my heart. 
Children are amazing- the progress they make physically, the changes in the way they think and do things.  Today Erika received a gift from a dear friend of mine- a beautiful draw-string purse and bracelet.  Erika was so proud of herself for being able to figure out how to open and close the purse herself. I just melt at the look of pride she gets.
Potty training begins soon.  I'm afraid.  I'm afraid in case it's not successful; it's a big step.  I don't want to put Erika in a position of failure.  I know my fears are most likely irrational, and she's most likely ready, but a little voice holds me back...it will be attempted this month.
As a parent, looking back years from now, when Erika is passing her exams and looking to borrow the car on a Saturday night, how am I going to remember that little voice asking for a "big hug and kiss, Mama"?