Don't forget, dogs are a LONG term commitment. They tend to live for 10 to 15 years, they can be expensive (shots, exams, food, grooming, and illness or injury are always a possibility too). Then you have to consider them every time you want to take a vacation or need to be away from home for an extended period of time (like you leave at 6 AM and due to a hectic schedule, won't be back until 8 PM or later).
Then there are walking them in the winter (cold!) or the height of summer (hot!), they may have accidents in the house (even housebroken pets pee on the rug on occasion. They can also get sick, up-chuck is so much fun to clean!).
Now I'm not telling you all this so you change your mind! Dogs are wonderful additions to peoples lives, and even with all the above drawbacks, I'd never NOT have a dog in my life. But these are all things that can lead many people to change their minds and send the new pet to a shelter in a hurry.
Just make sure you think through your decision. It's not fair to you, your kids, or the dog if after 6 months you decide it's too much trouble/work/money/mess to deal with.