I've always believed that there are millions of people in this world who would be willing to work harder than me if only they had the opportunities I have been given in my life. To not take full responsibility for my life and work as hard as I can to achieve something feels disrespectful to those who WOULD if they had the chance. I know that may sound a bit cheesy, but it's been an important driver in my life since I've gone solo.
I had a tough time finding a cofounder among my peers. Even the most entrepreneurial of them, people who had started things in college, are still far more inclined to go to work for someone else (especially with an offer in this job market). While I know there's a myriad of reasons, I think a most would rather go somewhere where all of the responsibility is on them. If you mess up at a big company, there's hundreds or thousands of others that shoulder the fallout. If you mess up and you're one of 2 or 3 or 4 people....
My point is that it takes courage to start your own company no matter what age you are.
32, married. As of yet I have no offspring, but that's going to be corrected. Still, I lurked and commented here, always with the 'Ahhh.. If I'd be without ties and responsibilities once more' thought.
I cannot tell you how glad I am to read that someone with arguably more responsibilities in life and a bit older than me (another point that is rarely coming up here) gives a damn about conventions and prejudices and just joins the otherwise ramen-eating, single, < 27 crowd.