I am currently bootstrapping a startup (http://www.wellhubstudios.com) while working at another startup and have a 1 year old with another child on the way. Couple tips that I picked up along the way:

1. Patience. Building a company is a time-intensive process that can be frustrating when family is demanding a lot of your time. Just focus on the goal and slowly pick away at your giant todo list for launch.

2. Its Good enough. Sometimes it seems like things are not moving forward or moving forward at a glacial pace. At these times I try to switch gears and say to myself "whats here is good enough for V1".

3. Time Management. I work 8-5 at my job. Come home and hang out with the family from 5-10. Then work on my startup from 10-1 pretty much every night. This takes both discipline and the ability to handle being a bit sleepy.