I can't stop crying :(

I'm a huge dog lover, I always have been. 
I got my 9 year old husky a number of years ago and she honestly is my world. I adore her and she understands me. After we had her a couple of years we decided to get a puppy. There were no problems at all at first but now that the puppy is an adult she's become very dominating. Both are spayed females. Every 2 months or so they'll have a fight just totally out of the blue and it scares me to death. 
I can normally tell when it's coming as they tense up and I can normally stop it before hand but on a very rare occasion it'll break out like crazy and me and my partner have to split them up. It's difficult. Especially scary if he is out and I'm on my own. My older dog isn't the fighting type and she will walk away once we get the young one off her but the young one bares a grudge and will be off with her for a few days after. Neither dog is agressive to people or in general it just seems to be a dominance thing. What scares me is, I'm pregnant and I'm worried if fights break out and I'm at home with baby, we have baby gates so the dogs will never be near my baby but I just don't want them to turn on eachother. Giving one away is not an option and as I said these are rare occurrences. It's just happened today and panicked me. :( anyone a dog behaviouralist? I've read everything and understand everything but every few months this happens and scares me..