Jodha was Akbar's first Hindu Rajput wife and nobody knows which number wife she was, because Akbar had married many women before his marriage with Jodha and even after it. Akbar had many children before his marriage with Jodha but most of them died in infancy, including his twin sons, Hassan and Hussain. Salim i.e. Jahangir was his first surviving son. Akbar had two senior queens, the first one was his first wife Ruqaiya Sultan Begum, his first cousin, the daughter of his paternal uncle and a Mughal princess, she was childless.
Salima Sultan Begum was the second of Akbar's two senior queens, she was also his first cousin, the daughter of Akbar's paternal aunt, Gulrang Begum. She was the mother of Akbar's second surviving son, Murad. Akbar had married her because she was his first cousin and was also a very talented woman.
Abdul Rahim was not Salima's son, he was Bairam Khan's son from his other wife.