I wonder if Basil was really fighting.
I recommended the catfinder thingies in the beginning of the thread, if you had one you could just walk through the neighbourhood until you beeped her. I have lost count of the times I have done that.
When she come home, buy some.
I think the chances are good that she is indeed hiding out close to home.
I don’t have any further suggestions that haven’t already been made in the thread; but will be watching in the hope of success, or at least of sightings.
Yeah, cats mating can get pretty noisy, too. Though there may have been tomcats fighting over Basil (who was quite possibly mating with somebody else while the fighting cats were distracted by each other.)

I wonder if Basil was really fighting
Haha, no, she was out getting laid. Cats are really noisy.
I was just naive, and thought she was male.
She’s outside. Just spotted her. She was crying in response to her brother.
So she’s OK
Now to lure her back inside with treats… it will be hard because she is not ready for close human interaction. Treat bribery might well work.
At least I know she is nearby. Her poor brother is distressed. And I am sure she is too.

She’s outside. Just spotted her. She was crying in response to her brother.
So she’s OK
Whew!
And if she’s stayed close this long (or moved off and already found her way back), then she’s unlikely to actually get herself lost. She’s staying in known territory: wise behavior on the part of a cat, and many of them will do it.
Maybe her brother will succeed in calling her back in. A brother and cat treats, who can resist for long?
I wonder if you put her brother in a carrier and set it down near the open door where she could hear and see him, she might venture inside to him? Then you might be able to slip behind her and shut the door before she bolted.
My previous cat, St George, hated that carrier with a passion. He fought me with teeth and claws if I brought it out. I mean, fair enough to him, I used the carrier to transport him in an aeroplane for over 2 hours, twice.
I don’t want these cats to associate the carrier with unpleasantness.
I mean, its not a bad idea. The boy will attract the girl and I can lock up the entrances.
My feeling is she might come in tonight- doors are open, food is available, and she’s scared of the great outdoors. So first thing tomorrow: check the food dishes. Then close the doors. Then search her normal hiding places. Let the other cat out in the house, to see if she is around.
If not then re-open the doors and banish cat 1 back to the bedroom. I cant lose 2 cats in three days.
Catio. We didn’t want our cats to run free so I built a catio adjoining the house, accessed through a cat/pet door. We put a large storage container out there with cat litter. Cats love it and no litter smell inside.
ETA: Something like this.
We even put a bird feeder nearby, they are endlessly entertained.

Forgive me if I’ve missed this, but do you have a Feliway diffuser for calming pheromones? A pheromone spray for the areas where they hang out? Perhaps, if he’ll tolerate it, a calming collar too?
Can confirm they help.
I do not have that option. The house in which I live is going to be demolised (mostly) and rebuilt.
Neither I or the cats will stay during that period. I am not putting myself through that, let alone the cats.
I will rent somewhere, probably close by, if I can find a cat friendly local place.

If not then re-open the doors and banish cat 1 back to the bedroom.
In the opposite order, of course.
Here’s hoping you find her curled up in a favorite indoor spot in the morning.
Or, better yet, that you’re woken up in the night by hearing her carrying on a conversation with her brother through the bedroom door – and that when you sneak out to close the outer door, she either comes to you or runs further into the house.

I do not have that option. The house in which I live is going to be demolised (mostly) and rebuilt.
Are you moving back into it afterwards? And, if so, can you get a catio built as part of the rebuild?
No, it belongs to my sister, and she will move in.
I need to locate some rental, and negotiate with the owner about a catio.
The fugitive cat seems to have eaten the food I left outside, (Hills Science Diet dry food) but not her prefered wet food that was inside (with the door open)
She’s like Shrodingers cat. I don’t know if she is in the house or not, and she has a Phd in hiding.
Can you put a harness on her brother? He may be able to find her.
Try the harness inside the house first, though; and make entirely sure that he can’t squirm out of it.
– but at least it might help you find out whether she’s inside.
It really doesnt help that neither cat is very vocal. My previous cat was identified by the vet as a burmese cross. He was loud, as loud as a Siamese.
These two are not vocal with each other, and barely meow. Some small chirping.
I think my strategy is this:
Keep cat 1 in my bedroom. He’s OK there. I did let him out on a tour, but he did not locate his sister.
Place food in the lounge. Cat 2 escaped the bedroom before and I decided to move Cat 1 and myself there as that was where she was hiding, so it is an area she is familiar with. Monitor the food and water levels.
Place food and water outside, at her (supposed) point of exit. The food bowl has been emptied twice now. I cant be sure if it is her or another local cat or even squirrels, the dominant local outdoor cat is really well fed and suprisingly chilled with other cats
I think it is her eating and drinking.
Find a trap… move the food and water in. Wait until she’s used to it. Then trap her and straight back into the bedroom.
I may catch the local dominant cat, but he’s a sweetie, as is his owner. He’ll complain but bribery is still an option for forgiveness.
Also, I guess, pray for rain. Cats generally would prefer not to be wet and cold. I"m leaving the front door open next to her food.
Are there any news?
The trap is out, but not triggered yet
I put a towel inside, some food and covered the whole thing with a piece of cloth. Hopefully today she’ll get hungry enough.
Took the trap back on Monday, after no success. I thought she was gone for good.
Naturally I spotted her again, this morning, 03:00… her brother was agitated and he woke me up crying at the window. So I was out in the garden naked, with cat treats looking for her…
Cats. You cannot predict them!
I’ve given up for the short term. I’m going to keep feeding her in the same place. I know where (more or less) where she is hiding, but it is totally inaccessible
She will get food as usual then the trap will return, probably in a week or two.

I know where (more or less) where she is hiding, but it is totally inaccessible
Is it somewhere where you can put cat treats right by the entrance, then sit very quietly a short distance away for some time?
If so, and if/when she comes for the treats even though you’re there – do not try to grab! If you miss, you may not get another chance. Put treats where she can reach them by only sticking her head out. Sit near the spot for as long as you can manage. Try again the next day. Once she’ll stick her head out, after a couple of days like that, move the treats very slightly further away from the entrance; and so on.
This may be more timeconsuming than fits into your life.
Well.
Good news and bad news.
I woke up at 04:30, and she was in my bedroom, as I feed the cats in the en-suite (because they are supposed to live inside…)
She has eaten all the food I put outside for her (or another cat has) so she was probably hungry.
Unfortunately, I had two doors open to the outside. I closed the first quickly, but the other is halfway across the house, and I am pretty sure she departed before I could close that one
So she knows how to get in. She knows where the food is. And while still extremely skittish she is not afraid to come inside, even when I am here. So that is good.
This is indeed encouraging. She probably came in because she thought you were asleep – but at least she came in.
Maybe just put the food inside now, although close to the door to start?