Is there a problem?

Hi. Im having a little bit of a problem with one of my cats, and was hoping someone can help me.

We have 4 cats. I know, its a lot. They have plenty of room though (our home is very large) and they are all very healthy and very well taken care of (I'm a bit paranoid so they get a lot of vet visits).
Our first cat, Jelly-Thyme was a stray I found 3 years ago, who was very nice. I was planning just to keep her till her owners found her (I put out ads and everything) but she ended up with me.(female cat)
Our second cat Tweek, was a 6 month old kitten we adopted 2 years ago with an extra toe and claw on all her feet. A girl I worked with had taken in a pregnant cat and Tweek was a kitten they couldn't seem to find a home for and was going to send to the pound. I couldn't stand that idea so we took her.(also female)
Our 3rd cat, Odin, was an abandoned kitten who we bottle fed. He was adopted by a good friend of ours who ended up moving in with us as well, so Odin stayed. Hes 8 months old. (Male)
And our newest addition, Louchen came just a few days ago when someone asked us over and over to take in this very sweet kitten. We didn't want to keep him since we have our 3 cats already, but hes very sweet and Odin and him because very fast friends. (Also Male)

The problem is with Tweek. Or that she just acts differently then the other 3.

Tweek is very picky. She will only lay in certain areas, and only let certain people pet her at certain times of the day. For instance, my husband can pet her almost anytime, but I can only pet her if shes laying in her special chair. She very very rarely wants petted by anyone and for the most part anti-social (except for my husband).
She also started to let the other 3 cats eat before her, while she waits in the corner. We ended up giving her a bowl of her own which she'll eat out of until any other cat comes around, then she just backs away and goes into her one of her spots.
She does play with toys and with people in toys, which is not a problem. But, when the other cats get involved she seems to distance herself and stand in the background just watching. The same with treats. We have to give the other cats treats, then walk hers over to her, then guard the other cats from stealing her treat away (she takes a while to eat it).
And the final problem is every so often (at the most, once a week) she will pee in our main bathroom (but never the one in the master bedroom or any other room). Just the one room. We have repeatedly cleaned and washed everything with the special soap from the pet store, but she still once in a while will do it. Its gotten a little more frequent, but the vet said it wasn't a health issue.

I might just be paranoid, but I can't help but think shes unhappy, or something is wrong with her. She reminds me of the shy kid on the playground just watching everyone else play. Am I being an over-reacting mother, or is there cause for concern.

Sorry this is such a long long post, but I wanted to make sure people had all the information they needed. Thank you for reading and helping

Hi and welcome to TCS !
My first thought is that she is stressed. She sounds like she simply isn't as social as the other cats and prefers her space. Finding particular places to sleep or rest, wanting to eat separately, irrational moodiness, avoiding interaction with the others are all signs of stress. Especially the peeing outside of a litter box.
How many litter boxes do you have? When did she start to display behavioral changes? With 4 cats there should be atleast 3 litter boxes in different areas of the home. If it is possible to put a litter box in the bathroom she sometimes pees in, this would encourage her to use the litter and give her space. Some cats simply don't like sharing their home, their litter, their food, their water with several other cats and when given no choice, become stressed and anxious. I would also try to give her the space she is asking for, give her separate food and water, give her individual time and attention.

It sounds to me like she is a stressed out little shy kitty... Three other cats might be too many for her... Did this behavior start after a new addition?

Can you move her food to another room? Maybe adding another litter box to that room would be an idea...

we have 4 litter boxes, in 3 different places. We tried putting a littler box in that bathroom, but theres really not a good space for it (people kept falling over it). she does have a few spots (such as her chair) that the other cats never bother.
The new addition really didn't change her behavior much. Shes been like this. Its just starting concerning more since I thought "well, its just her personality" but seeing how the other 3 are all act so differently I thought it was time for some help.

Thank you both for your replies! I hope the new info helps.

I don't know how to help you... All I know about what you are describing is that she is probably meant to be the only cat in the house... Have all the love, time and attention...

I have 9 cats, they pretty much all get along or some just tolerate each other, but I have one that is exactly like yours. I also have to bring her food to her in a special place and watch to make sure nobody else takes it from her. She also wants petting on her own terms. I have to be sitting most of the time. The others know she's like this so sometimes they try and chase her. She's small so she has her places that the others can't get in. She loves laying in the sun until one of the others want to lay there then she runs away and lets them have it. Unless I'm there at the time and run interference. Its her personality, every now and then she plays with a toy but other than that she stays to herself (three of these cats are her littermates). The bathroom issue with her I don't really have but she runs to the litterbox while no one is around. Lee seems happy enough. Its her personality. Good luck.