Hi Melanie,
I have two girls, ages 9 and 11, and balancing my time is always a challenge. Although the girls were a lot of work when they were babies and toddlers, they are still a lot of work because I want to be involved (or at least present!) at their various sporting events, music recitals, school events, etc. One of the best things, for me, about my job is its time flexibility. I'm able to work at home when I need to and pretty much organize my work hours around my kids' activities. This often translates to my working from home before the kids go to school, working at my office while the kids are at school, focusing on my kids' activities as necessary from about 4-8pm and then working from home after that.
The biggest sacrifice is not having all the time I would prefer to focus on my own hobbies. And in order to find some time for those, not to mention time with my husband, my house isn't as clean as I might want it to be - ah well... ;)
Luckily, since I've had kids, I've worked with other people that understand that balance (most of them have kids themselves) and so are very flexible about timing meetings etc. So, I haven't had many problems in that regard, thankfully.
Best,
Christina