I over edited my post on the loss of my sweet Sian while in a state of shock
Sian seemed fine on Wednesday but the vet explained that sometimes cats can 'hide' their health problems until they reach a tipping point, which is what happened to Sian. I had been combing her, giving her flea medication, doing everything I can both inside and outside to take care of the flea infestation, but it still wasn't enough. I feel like the worse mom on the planet, right now. The feral kittens, well, they were outside and I grabbed them as soon as I saw there was a problem. Sian just didn't exhibit any issues until it was too late.
My brother went with me to the vet. Sian had flea related anemia. They gave her a subcutaneous rehydration treatment, anti biotics and flea medicine. It took a long time because her body temperature was low. When we got home I cuddled her for about an hour and then got her settled in to a warm, safe place and then I left her, for just a few minutes, hoping she'd fall asleep.
I wanted to change clothes and decided to check on her on my way to my room. She looked up, took 4 or 5 very deep breaths, and then she was gone. I thought maybe she was just having a stress reaction so I was trying to comfort her when she died.
She is buried very close to where I first saw her. I buried her in one of my favorite t-shirts and place a Passion Flower and Queen Anne's Lace flower on top of her.
Thank you all for your kindness and compassion.
I have to stop, now, because I just can't stop crying. This has hit me harder than I ever expected.
= new reply since forum marked as read
we all were able to know Sian, and we grieve with you. 
I'm stunned, such a precious baby. You should know that you did everything you could for her, & she knew how much she was loved.
So very sorry to hear this. Yet, I was glad to hear that you were with her at the end. My deepest condolences to you. It is so hard to lose a fur baby.
I didn't get online today until a little while ago, so I'm just finding out. I read the thread about Sian being ill and got very worried; then I immediately read this one. I'm still in shock! 
Please, please, please don't be too hard on yourself, Siwsan! You did your absolute best, but life plays cruel tricks on us sometimes, and this is one of them. This is NOT your fault!
I know this is a deeply felt, heart breaking loss for you, but I hope you can take at least a little comfort in the love of your remaining fur babies and in the support you have here at DU. Take care of yourself, and please keep us posted. We are all pulling for you, really, really hard!
You loved her and did your best for her - that's what matters the most.
You did all you could do. I’ve read your posts for a while, and you’re a very compassionate person! Please give yourself some grace and some space!
One more
waiting for you at the Rainbow Bridge.
Our little ones are so close to our hearts and it hurts every time.
As much as Sian may have suffered in her final days, she was at peace in the end. Taking her last breaths as you lovingly held her. They certainly do leave their paw prints on our hearts.
I have been reading your posts for years. I remember Arthur as a tiny kitten. We have rescued many cats, mostly from shelters. I get your passion and love for them.
I remember a kitten you lost a few years ago and I cried and cried. I don’t know how you do it.
I’m so sorry for Sian. Her little body just couldn’t take it. Hugs to you for all your losses and all the good work you do for these innocent little beings.