The kids really don't get the whole concept of Santa and him bringing presents and all that. So before Christmas Isabelle and I were talking about what she hoped Santa might bring her for Christmas and I suggested that she write him a letter to let him know. 

" I should write him a letter? " she asks me quizzically

"Yes," I reply " you know Santa is a busy man and it's a lot of work to think  about what each kid would like the most for Christmas, so sometimes it helps if you write a letter."

" I should write him a letter and he will bring me presents?" she asks again

"Well, you have to be really really good too, " I say.

"OK, mommy, I will write Santa a lot of letters! I will write a I and an O and an S and a T and a..."

you get the idea : >)