Allah said ( interpretation of the meaning ) : { So We restored him to his mother that she might be content and not grieve and that she would know that the promise of Allah is true. But most of the people do not know. } Quran ( 28 : 13 )

Allah subjected the wife of Pharoah to convince him not to slaughter the baby perhaps he may benefir them or that they take him as a son. Then Allah prevented him from all the wet nurses so that his mother restores him. 

# Moses_ in_the_Quran