Job Advice: Stable job vs. Dream Job?

I currently work as a part time housekeeper in a professional environment and I've been there for 2.5 years. Recently, I've graduated college and have just gotten offered a part-time in my career field working in corrections. The hours in my housekeeping job are set for the most part except the schedule is so screwy that I can't find something to work with it. I'd like to go to my boss tomorrow and hand him my monthly schedule for my corrections job and see if he'd be willing to work with it since I know that he's short handed since my coworker recently left on medical and will be gone for the next few months. I need some advice because I'd really like to keep both jobs. I just feel like I'd be a fool to give up an opportunity in my career field...