Family visitor visa refused

Hi guys, hope you are well.
Please advice on my situation.
My sister applied for a Family visitor visa and was refused.
My husband is sponsoring the trip, 15 days, fully, we sent statements with more than 20K, we are both british (if that matters at all).
We wrote that she is supported by her husband and my parents, because she is a mum of 2 small children, and her husband + my father are giving her 400 quid in total in pocket money for the trip. We included her husbands work statement, 2 bank statements (current with salary incomings, and savings one with about $900 in it)
My father supplied 2 bank statements (1 with salary, and the savings one with more than $5.000)

She got a refusal stating: your husband earns £250 per month, and you state you spend £90-110 on living costs and that you have 2 dependent children. You state that your husband and father will give you $800 for this trip; that equates 4 times your husband's expendable monthly salary. You have not provided details of your father's business, employment or income. I am not satisfied that this trip is commensurate with your current circumstances. Given the above I am not satisfied that your circumstances are as stated, which causes me to doubt your intentions seeking to visit the UK..."

So, thinking they missed my father's statements, I wrote to them asking to reconsider. I asked if they missed my father's Salary incoming highlighted because that's what I understood was the main reason they refused- not seeing where money comes from. While waiting for the answer that took weeks, we reapplied with my father's properties documents, rented out money for flats, and employment letter.

Today we received the letter to the request, saying:
Your application has been reviewed by an Entry Clearance Manager and the decision has been upheld. The fact that you provided your father's bank statement was not in question in your refusal notice. You are free to make a fresh application but please note that in doing so you should address in full the reasons for your previous refusal. Each application is assessed on its own merits and no guarantee can be given as to the outcome.

I now think she will be refused again. We are thinking the worst. Maybe they think she shouldn't be travelling even if we in the UK are inviting and sponsoring her trip. Maybe they think she shouldn't be travelling because her husband can't afford it. Maybe they are just being nasty. They gave visa to my friend's unmarried 28 y.o. sister with a secretary job and no money. I think she had less ties to the country than my sister.

Do you think there is no hope?
Thank you for your time

By the way, has anyone received a message from British consulate in Istanbul that they RECEIVED the document next day AFTER they already made a decision? So, visa refused on the 2.04 but letter of receiving documents is from 3.04. How can this be right?