Can anyone tell me what makes a blog popular?

1. Write interesting, useful, and original posts.
2. Write a lot of them.
3. Get other people to link to the posts they find to be the most interesting and useful.
4. Write some more interesting and useful posts so the people that click on your friends’ links stay to read more, come back later to read more, and link their friends to you.
5. Repeat from #1 as often as possible.

This is a theory, but I think if you have a lot of friends and family that will leave comments it may pick up in popularity. I have a belief that if people see something is popular they’ll want to join in, also.

Sadly, I don’t have any friends or family that will leave comments on my blog.

Write for yourself. Building an audience may (or may not) come in time. But if you write for yourself and not others, at least the end result wouldn’t be a big waste of time and effort.