"Mike, is Rania your grandmother?"
Translation:يا مايْك هَل رانْيا جَدَّتَك؟
Even though your sentence here somewhat acceptable (more in the dialect realm rather than standard Arabic), but the logical order follows the sentence above. Because we are asking about "Rania" herself and her relation to Mike.
It's like in English, in such situation, you might rather say "Rania is your grandmother" than "your grandmother is Rania"