If it makes you feel any better, I just did the same thing 4 weeks ago. I adopted a lab retriever. He is 10 weeks old now and keeps me quite busy. I can't really afford it but I'm hopeful that I will get a job soon to pay the bills. Vets can be pretty expensive. It's really bad. I'm just charging everything for now.
The funny thing is that I have all these health issues that I should take care of but I don't because I don't have the money. However, I just went ahead and got a dog...people think I'm insane but my son deserves a dog. He's been begging for one for the longest time. Pets are so wonderful to have...They bring so much happiness...I just love them!!! Money for bills and yarn will come eventually.
Your kids will have a blast!!!