Item statistic "CreatedBy" returning empty string

Question

I'm trying to get the creator of an item, but when I access the CreatedBy property, it returns an empty string. When I debugged I could see the all the other fields were populated, but not the CreatedBy:

var contextDatabase = Sitecore.Context.Database;
Item blogPost = contextDatabase.GetItem(data.ID);
var creator =  blogPost.Statistics.CreatedBy;

I really don't know why it shows as empty. Any idea why?

Edit: In the content tree, in the statistic field section, the CreatedBy is there:

Answer 1

"Statistics.CreatedBy" property does not return standard values.

To fix this problem please use : blogPost.Fields["__created by"].Value

Statistics.Created use next code:

private string GetFieldValue(ID fieldId)
{
    Field field = this._item.Fields[fieldId];
    return field.GetValue(false, false) ?? string.Empty;
}

where field.GetValue has next parameters

public virtual string GetValue(bool allowStandardValue, bool allowDefaultValue)