- You may be looking for Maximillian Acorn from Mobius Prime. Or you may be looking for the Mobius: X Years Later version, Maximillian Acorn (MxYL).
The retired King Max with his grandchildren Manik and Sonia
Maximillian Acorn is the father of Sally Acorn in the alternate future reality. He is also the father-in-law to Sonic, as well as the grandfather of Sonia and Manik Acorn. He was presumbably killed when Mobotropolis was nuked by their universe's Dr. Robotnik. (StH: #75, IYF)