It is so sad to read this kind of stories, I have been in the situation similar to this and I know how hard it is.
For you and your family, you have mentioned that you don't know what to pray. Just talk to God like your best friend and tell Him all your sorrows, your worries and ask Him to take over this burden. Ask His will and surrender everything to Him.
For your mother: hello ante, I pray that God will give the healing you need. Pray to God, talk to God, ask forgiveness for all your sins and accept Him as your personal savior. Everything is possible to Him, He could give miracles but please know that His plans is better than ours.
I also pray that God will provide all your needs especially financially.
Thank you so much for your heartful message and support. Especially your prayers for my mother. Gid bless you too.