Wow that is a lot to be left with! I am very sorry for the loss of your sister.
And despite the sad circumstances welcome to Yorkie Talk.
Here is a site you can go to for some refreshing of whelping necessities and situations.
Dog Breeding and Canine Reproduction by Debbie Jensen. Dog Breeding and Whelping guide for dog breeders.
I'm not too sure how large your gal is. If she is small boned and weighs under 5lbs things could get dicey!. Pelvic structure and the number weight and size of puppies will be key on whether or not she needs a C section.
You could be close to a due date or maybe 2wks away. Is there anyone that can help you out both financially and with taking you to the vets?
I'm not sure if you've kept any of your previous whelping supplies but you will need some for sure. I would bank on puppies coming sooner rather than later, so a constant watch of your gal is in order, as well as gathering up those whelping supplies. The website will have a list of what you will need.
I would start feeding her a high quality puppy kibble right away. Lots of water etc. Do you have a thermometer to take the temperature of your gal?
You need to find a space for her whelping. Make sure it is draft free and warm! Also you need to be able to keep her and her pups separated from the male, especially during the early days.
I do urge you to try to find a vet who can take you in sooner rather than later. Family/friends may be able to help out?
I do so hope that you are able to prepare and good luck finds you and your gal safe through this.