Career in the Medical Field

You are right with kids as young as yours it would virtually be impossible.
My friends daughter is going for Nurse Practitioner and my friend has her
grandson with her overnight for three days during the week. It is the only
way she can do it. The other days she has a babysitter. How about
an echo tech, ultrasound tech, for right now. However, even that entails
long days, but doable. My DIL did that. She makes good money now.
When your kids get older and more self sufficient you can follow your
dream. Whatever you do, do not give it up. Good luck.

P.S. My daughter is a surgical tech. Went to school for a year. It was a
fast paced two year program in one. She works in the operating room and
loves it.

The online degrees you mentioned aren't worth the money you'll spend to get them. Don't waste your money. Nursing -- and all other health care jobs -- are intense and hands on. There's just no way to get around it. If you don't have the time or desire to go back to school right now, how about getting a job as a nurse's aide or a hospital tech for now? It's not glamorous and you'll spend a portion of your time bathing people and lifting them from one bed to the next, but at least you'll be in the medical arena and learning more about what you want to do when you have more time.

I suggest you start out with something that requires less education. Then when the kids are older you can go to school to follow your dream.

My daughter is a medical assistant. I know, that's a long way from being a nurse practitioner but you'd be in the field gaining experience. Her training took a few months during regular hours. She now works days in a doctors office. She loves the interaction with patients.

If you want in the medical field why not go for a cna? Here its a 6 week program... 3 5hr nights a week. That includes clinicals. Its not a nurse like you want but its only 6 weeks training.. plus taking your state test. You would be able to get your foot in the door and then when your kids are a little older you would have some training under your belt and then be able to go back to school for a nurse.

I agree with everyone here that your best bet at this point is to go for a lesser degree, like a medical assistant or CNA. You'll be able to get through the degree faster and get into a job that doesn't have so many off hours.
I have a friend with two young girls who received her NP degree a couple of years ago. It took her a while to get it. The schooling and the clinicals took a lot of time away from her family, and she had to travel around the state for some of it, so her family could watch her girls while she went to clinicals. In the end, she was very happy with her decision to do it, although her first job was in a physician's office in an urgent care capacity. She worked long hours even then. She has since moved to another state and found a great job in a physician's office seeing her own patients. I don't think her hours are quite as bad, but she still has to take call, which is something you need to think about as well. Who will be there for your kids if you have to see a patient in the middle of the night? (I'm not sure how it works for NPs, but my husband is an OB/Gyn, and when he's on call, he has to be ready to go into the hospital if he's not there already, even in the middle of the night.)
If you get a lesser degree at first, you can always go back to school and get your bachelor's degree/NP when your kids are older. Good luck! If you have any questions about medical school or residency, you're welcome to send me a private message. I've been with my husband since undergrad, so I've experienced everything. He's now a practicing OB/Gyn.