Ilya Frank came from a family that any Jewish grandmother could be proud of. His father, Mikhail, was a mathematician and historian. His uncle Simon was a philosopher; another uncle, Leon, a poet and and artist. (Maybe a little less proud of Leon.) Brother Gleb was a biophysicist. But Ilya outdid them all: he won the Nobel Prize for Physics in 1958!
About those uncles: Simon was exiled from the Soviet Union, went to England, and became a Christian. Leon also ditched Russia, for France. Ilya's father stayed, but not before converting to Christianity himself.
But what about Ilya, you ask? Surely, a scientist of Jewish heritage in the Soviet Union would not be a Christian? Alas, not exactly. Raised Russian Orthodox, then agnostic for a long time, Ilya returned to his religious roots as his life was winding down.
Did that Jewish grandmother stop spinning in her grave yet?