Sometimes its just about treating it as if it were a job. Most people write as a hobby, those are the people that stick to one site usually, but others, who want to make a living if not now, then in the future, will often refuse to put 'all of their eggs in one basket' and write for multiple sites. It's just the smart thing to do sometimes. I've never tried Squidoo, but I have tried sites such as DooYoo and Helium and have managed to juggle all three at the same time. As someone else said, it's all about priorities. If you were working 8 hours a day, you would have to. That's the mindset to be in.
You may have kids, but people that work full-time also have kids. It's the same field. Treat it as a full-time job rather than as a simple hobby and discipline yourself to succeed, and you surely will.