Mommy!Fail

So this is me, feeling like the craptastic mama supreme.
Shortly before Snapdragon was born, my mother took in a pregnant stray cat.
No, really. She was that foolish. It wasn't even a soft or pretty cat.
In defense of this fourlegged creature which would be christened "Tiny," she was a friendly cat.
Well, as I mentioned, Tiny was with kitten, and I'm sure you all know how that happened, hanging out with some friendly Tom. Sadly, Tom wasn't the only fun guy Tiny had been hanging out with. No, she'd been hanging out with ringworm.
Now, for those of you who don't know, ringworm is a kind of fungus. Sorta like yeast. Ringworm likes to live on your skin and heals from the center out as it expands outward. It starts off looking like a pimple which blisters. So innocuous you'd be likely to ignore it until the center de-red-ified and keft you with a largening telltale ring of red. Mostly, that's what it looks like. It glows under a "blue light" I always called them black lights, but the vet says blue, so we'll go with that. If it gets on your scalp it behaves like cradle cap, causing scaly patches. Oh yeah, and your hair will break off at the contact point.I almost forgot to mention that part.
So Mongoosine loved Tiny, and no one ever thought it might be a problem that she cuddled Tiny. Then she started cuddeling the kittens when they were born. No one wondered why Tiny had a bald spot. She'd been a stray and cats who scratch at wounds tend to have bald spots too.
Then no one wondered too hard at why the kitens had bald patches. We figured that Tiny, being a slightly neurotic new mamakitty was probably over cleaning.
But then Mongoosine got the first of what would collectively come to be known of as "the spots." Her first spot if "Scourge" was showing and identifiable by Mother's day.
Since then we have been waging war against the scourge. She has been fighting it like mad and she hasn't been alone. My mother, father, spouse, aunt, iuncle, their three children, and my nephew have all contracted the scourge. Mongoosine was the only one who was showing signs of improvement. As a matter of fact, this weekend she was declared scourge free and the interaction with Snapdragon interdiction was lifted.
Today she was feeling happy and having fun with her grandmother. They put sun-in in her hairand she played outside. Later this evening, as my mother was admiring the highlights from across the room she saw something funny. She called Mongoosine over. It was something whitish. My mother was confused.
Alas, it was her scalp where her hair had broken and fallen off leaving a large bald spot.apparently, we mised a spot.
When she called, I used explatives best not typed. I am very unhappy. I am angry, I am hurt, and I don't know how to make this stop. But I also feel terribly guilty that I've been so wrapped up in Snapdragon, I didn't realize Mongoosine had scourge on her head before it became something which although she will claim doesn't bother her, is ultimately stigmatizing for a tween.
This was total mommy fail on so many levels, starting when my mommy let mommy cat in to start with.