The story is a bit different in Islam. Ibrahim is sent a dream to sacrifice his son (it’s never explicitly said whether this is Ismail or Isaac, but the majority Sunni opinion as far as I’ve read has it that it was Ismail). Ibrahim goes to his son and tells the dream. The son agrees to submit to the will of God and they set up the sacrifice. The son is never bound, but lays down willingly. When Ibrahim takes the knife and begins to follow through by cutting the throat, though, he finds that his son has been replaced with a sheep and he has sacrificed a sheep instead. It was a test of faith for both Ibrahim and his son.
So, really, the sheep is sort of there incidentally. The idea of the sheep being a proxy sacrifice for the son doesn’t really appear the same way that it does in the Torah.