Gen 25 - If Abraham dealt unfairly with Ishmael, would Ishmael have attended Abrahams's funeral?

Gen 25:9
Then his sons Isaac and Ishmael buried him in the cave of Machpelah, in the field of Ephron the son of Zohar the Hittite, facing Mamre,

Gen 25:10
the field which Abraham purchased from the sons of Heth; there Abraham was buried with Sarah his wife.

The presence of Ishmael at the funeral of Abraham is very interesting. If Abraham had allowed Ishmael to be dealt with unfairly, would Ishmael have acted this way? It is likely that Abraham prayed for Ishmael when he disobeyed and this was the source of Abraham's distress. The act of casting Ishmael out was just, merciful, righteous according to Torah. Ishmael must have understood this also.

Gen 25:25
Now the first came forth red, all over like a hairy garment; and they named him Esau.

Gen 25:26
And afterward his brother came forth with his hand holding on to Esau's heel, so his name was called Jacob; and Isaac was sixty years old when she gave birth to them.

The name "Esau" means "the hairy one" and also implies red hair. This also provides a connection to his other name with is "Edom" meaning "red." "Jacob" means "he grasps the heel" or "supplants." These two boys were named by first impressions.