She died and left behind four sons, a daughter, a brother and grandchildren

Praise be to Allah.

If a woman dies and leaves behind four sons, a daughter, a brother and grandchildren, and her sons and daughter were alive at the time of her death, then her estate is to be divided between the sons and the daughter, with each male getting the share of two females, because Allah, may He be exalted, says (interpretation of the meaning):

“Allaah commands you as regards your children’s (inheritance): to the male, a portion equal to that of two females”

[al-Nisa’ 4:11]. 

There is nothing for her brother or her grandchildren, because they are deprived of a share by the presence of the sons. 

As the male gets the share of two females, the four sons get the share of eight females, so the estate should be divided by nine, with the daughter getting one ninth and each male getting two ninths. 

So the daughter's share = the estate ÷ 9 x 1 

The share of each son = the estate ÷ 9 x 2 

And Allah knows best.