I will definitely pray for your Dad.. I know this must be a very tough time for you nd your family, but i'd just say.. Dont loose hope! God is watching us nd listening to every one of us, so i pray to God to give ur Dad, health nd life! Just remember, Allah is not unfair to anybody in this world, jo hota hai hamesha achey ke liye hee hota hai, so all this is happening as Allah is protecting you, your family nd your Dad from bigger problems.
Just have faith in God nd im sure ur Dad will recover very soon (InshAllah) 😊 My prayers are with him :)