Yeah, it´s amazing how much this can make for the very poor people in the country. Not much, but she might get it rolling. Unfortunately it sounds like she have taken on a too big burden on her shoulders.
First, we can not consider this as a newfound wealth. This is an amount to help people a little bit on the way. Even for a poor family, 10k baht will only last about 4 months. That, is not something we can call wealth.
After that, I wonder how this poor woman can be responsible for all disabled siblings as well as 3 grandchildren? There must be other people around that can chip in. Are all 3 siblings single, and not married to a person who actually got a work? I assume they do neither have any other relatives, like children of their own that can help them. And the 3 grandchildren??? Where are there mother and father? Just very nasty to run away and let a poor old person take all the heavy lifting making it float.