New born diary

When I was told I'll became a father I started a diary about how I feel about it, writting short essays directed to my child to be, trying to write down my feelings more than the facts or historical events. My goal is to give it to my son when he turns 21.

I suppose it is common, I woukd like to know if there are recomendations about this, how other parents write down other diaries or histories. It is written in third person style? One essay each month, justo to not end forgetting.

Does anyone received something like this from their parents?

Any suggestions and experiences are welcome.