My cat is throwing up

Question
My 2 1/2 year old female DSH cat started throwing up today.

She is indoor-only, all shots up to date, and otherwise pretty healthy (apart from weighing in at almost 10 lbs. in her recent checkup 2 months ago). She is the middle of 3 girls (all of them strays that were adopted at a young age) and is the "alpha" of the house.

This morning she threw up a few hairballs, and after she had breakfast (just under 1/3 cup - they are fed 2x per day), she threw it all up. I noticed she was pushing the other cats out of the way and eating their food as well as her own (not uncommon for her). She threw up a few times later as well, small amounts, mostly liquid (no foul smell), in each room of the house.

Due to my fiancee's job, we have moved twice in the last six months, and I'm wondering if the stress of the most recent move (1 week ago) has something to do with this? She is not in any way lethargic/listless, I have not seen any diarrhea, and she is otherwise acting normally. They are fed Purina Good Life All Ages (Chicken, Brown Rice, and Garden Greens) which they all seem to love. I tried a different food in the last few weeks (Castor & Pollux Natural Ultramix Indoor) which none of them cared for, so I switched them back to the Good Life. The other two cats (3 1/2 y.o. & 1 y.o.) are completely normal. The water bowls are changed daily, as is the litter, and nothing seems out of the ordinary.

If she is still vomiting tomorrow, I will contact the vet, but was hoping there may be something you can recommend?

Thank you very much!!

Answer
OK, well there are a few thing here that might or might not be a cause, but certainly need to be addressed.

Firstly, changing any pets food this often is going to cause digestive upsets, including vomiting and usually diarrhea. So you need to not change their food so often.

Secondly, the food you have them on has way too much protein for adult cats. "All ages"cat food means that it is formulated for a kitten and they are too old to be on kitten food. The law states that's how this food thus labeled must be formulated.

Thirdly, yes, moving is very stressful to a cat, the older the cat, the worse the stress is on them. Cats do NOT like moving around much. Some cats love it, most, however, do not. Siamese cats are probably the biggest exception to that rule. I know you cannot change that, but keep in mind that it is a big deal to your cats.
Now I know one of the cats is older, but apparently it doesn't bother her as much.

Get your cats on a healthier brand of food made for adult cats. Science Diet Indoor cat or adult formula is the best you can buy for the money. Each cat will need less food so that your dollar goes further with it. It is highly digestible so there is no waste and it makes your cats stool much smaller because of the digestibility. The stool also barely has any smell.
All SD formulas also address the hairball issue, so you don't need a separate food for that.

If she is vomiting in the morning you really need to get her to the vets.
Please let me know how she is doing later.