Personally, I think there needs to be one, anchor Twitter account, and it has to be YOU. Not the blog, not the company, but you the person. You can (and should) still tweet about the blog, the company, and the industry (because that's part of who you are), but if I don't see some authenticity, I won't follow. That's where you should build the relationships and the following. Then you can create some other, more branded twitter accounts that you use to automate dissemination of posts and other information. My two cents from a non-marketer but early Twitter adopter!

In my opinion, a mix the first two would be ideal. Your personal side will show your authenticity around parenting & family and show you have other interests, you can post occasional links to the blog of posts you would like to promote or that are doing well.

Finally, for occasional posts, that frequent retweet you AND other competitors/brands with positive messages and information should come from a separate business twitter account. Hope this helps or at least gets you thinking. I'm happy to provide any additional info via a followup call.

Personally I look at it in terms of the audience you are targeting. I first started with my personal twitter handle that covered a vast range of subjects and then found my followers and interest split between entrepreneurship, innovation and cloud computing/big data. As such, I created three twitter handles to address each and manage them in that respect to avoid crossover. For marketing purposes I would attach a different twitter handle for your blog and business to ensure followers remain loyal and interested. Keep your personal twitter handle to cross-pollinate tweets that serve many audiences.

Unless you have an already active company that has interesting just-in-time news or announcements that your clients want to hear.. like (hamburgers 20% off today) don't bother.. twitter is seen as a just-in-time news thing... Build it after you already have audience - Think of it as communicating to already active audience... not build a audience... Not worth the time.. or the effort..
Just my two cents
Steph