She is depressed. Cats do get depressed, which can lead to significant behavioral changes.

Lolo is used to having you all to herself, and your undivided attention. Now here you are coming around covered in Sophie's scent---in her space!!!

She's insecure, angry, and depressed, and may feel threatened and unsafe, as well.

Please don't try to rush things and put them together too soon. Defer to Lolo. Keep Sophie out of her space. Remember, as an indoor cat, Lolo has nowhere else to go--your home has been her sole territory and in her feline mind she's the ruler of the domain. It will stress her out to have Sophie pushed on her.

Please do some googling on this issue to see how to slowly integrate a new kitten into your home.

It depends on the personalities as to when, or if, they will accept each other. If you are lucky, they will bond and be friends. And that can happen quickly, within a week. Otherwise, the best you can hope for is detente and to tolerate each other. And sometimes, the new cat is not accepted at all, and may have to be re-homed. I've read about situations like that, too.

I second the suggestion for Feliway. And if Lolo is struggling during this time, and you detect changes in her mood, appetite, vocalization, habits, etc., then take her to the vet and get some kitty xanax.

Again, please be cautious in letting Sophie into the house and spreading her scent everywhere, including you. Lolo won't like that and it will likely cause her stress.

We've homed many cats--all strays and throwaways--and each time has been unique in how they adapt and learn to co-exist. The third one we took in became the dominate one. Kitty #2 seemed alright with the new arrangement, but kitty #1 never seemed to forgive us.

We're on kitty #8 now--and will possibly bringing in another one soon, so this is what we've learned through the years.

Good luck, I hope it all turns out well.