Pinot - I have been lurking all week as on blackberry that won't let me post, so so sorry to hear about Rosie.
When I was at uni I worked at a vet and someone brought in a kitten, probably about 2 weeks old then. He meowed all afternoon and I couldn't leave him there so I brought him home "for the night". Yeah, right! 14 years later he was still living happily at my mum's house. He was slightly cross eyed and a bit clumsy - the sort of cat that would jump for the couch and miss, slide off in an ungainly manner, check whether anyone was watching and march off, tail in the air in a "I absolutely meant to do that" sort of way.
Anyway, the weekend your kittens were born, Tyson was off his food and clearly off colour. Mum took him to the vet on Monday who said he had problems with his liver. He was on a drip, morphine, medication and had a liver scan on Tuesday. He died at the vet around 11am on Wednesday. Mum had an appointment with the vet to talk about his scan at 11:30. She is absolutely distraught that he died alone at the vet.
Reading about your kittens has made me remember the early days with Ty, when he was such a tiny kitten. We gave him porridge on a teaspoon at first. And, like yours, he was all purr and hardly any cat. 
I so hope Ginger and Meow continue to thrive, it's so fab to read about them every day. I plan to print this thread and send it to mum, I think it might also make her feel better about Tyson. Good luck good luck good luck!! You are doing such a wonderful job.