Raymer -
I'm not sure I follow what you mean. If you mean a pedigree chart that shows all siblings, that's highly unusual and the chart would be very VERY large (wide).
However, if you Select your mother's father, and then click on the Descendents icon shown in Chris' answer above, it will show up to 5 generations of descendents, I.E. your mother and all of her siblings, their spouses, and their children, their children's spouses, and so on; all on one list.
This of course, assumes that all of that information has already been added here on WikiTree.
- Mike