Would you choose advancing your carrier or choosing a desk job to be off work to pickup your kids?

I have the chance to advance my career further in the medical feild and get my EMT-B license. I was to do it so bad but I have 2 kids and due with my 3rd soon. Kids are 2 yrs (Will be 3 when the new one gets here) and a 1 yr old. I have to choose between advancing my career and doing 12 hour shifts (which is what I work now) or I can work up at the court house and get off my 5 pm to go pickup my kids from the baby sitters.
If I do EMS then I have my career set and will make a little more than working up at the courthouse. But if I do office work then my work hours are shorter, I make a little less and I'm around my kids more.

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