Introducing two kittens to a senior cat?

Hi there! I currently have a 9 year old sweet female cat and have been thinking about possibly adopting two kittens. I am still somewhat on the fence about this. I see a few pros and cons and was wondering what you all thought about it. Felice has been the only cat since we got her, though we did have some temp kittens stay at our house (which made her growl and stalk the door quite a bit) but they were only with us for a few days, 3 max. She still ate and used the litter box, and growled when she saw a kitten but it wasn't a "I must kill you!" kind of thing. She explored the room when the kitten was gone, she was tentative but not that stressed. She is somewhat active but not hyper active like a kitten hence my thought of getting two. They could play with each other and leave Auntie alone to sleep. I just worry it would be a lot of stress on her but also torn as I fell in love with two kittens who I would love to adopt from a rescue. I would plan to do a slow introduction, feeding outside the doors and slowly moving it forward for her to associate that smell as a good thing. Then have some site swapping, kittens would go to one room and Felice would explore the room in there. As well as having Feliway and of course more then enough litter boxes, and cat posts to help prevent resource guarding. My parents aren't sure either, we rent so we know how hard it is to find pet friendly housing but I don't think having 3 cats would make it so much harder to find a house then just one cat?

I wouldn't worry too much. Most cats, but not all, would like to have another cat as company. It won't seem that way at first as they are somewhat territorial to outsiders, but I think there is a good chance it will be fine after a month or so. I think there is also a better chance that she will accept kittens because they are less of a threat than an adult cat.