re: Cat Advice

We've had a similar story in the past. It will take time and don't let the kids (if you have any) get too upset if the cats hiss, scream, etc. There likely shouldn't be much physical fighting, but moreso growling, hissing, and tails that are fluffed out and standing up.

You will have to show Lolo over time that Sophie is part of family and act like Sophie is welcome to walk around house and is encouraged.

It may take weeks, sometimes months as some said. 4 cats at my parent's house. 3/4 got to like each other, but there's one sourpuss who just refused to accept the rest, but they are all able to coexist.

Smelling each other out is by far the biggest thing.
I would also consider SEPARATE litter boxes for a while too, and maybe separate food and water as well until they get along. Separate litter boxes are important because Sophie may not feel comfortable going in Lolo's box and will inevitably end up going somewhere else.