Need help?

My brother who is in prison until Jan of next year has one boy with his ex who is 5. Child protective services are taking the child away for neglect. She is a drug addicts, sleeps all day, never feeds her children(she has another 8 month old who is not my brothers), puts them to bed then leaves them ALONE for the night....she admitted to this all. Well they came to me and asked if I could take one or even both till she gets "help" or possibly till my brother gets out of prison. Even then, he would have to prove himself. 
I have a two year old boy with my BF of 7 years. I own our home but he does pay half the house payment. He says absolutely not, we cannot care for two more children but I want to cause if I can't, they will go to foster care. I don't want that. I do respect him but I just feel terrible. What would you do in this situation?