لَوْ أَرَادَ اللَّهُ أَنْ يَتَّخِذَ وَلَدًا لَّاصْطَفَى مِمَّا يَخْلُقُ مَا يَشَاء سُبْحَانَهُ هُوَ اللَّهُ الْوَاحِدُ الْقَهَّارُ
[39:4]
If Allah desire to take a son to Himself, He will surely choose those He pleases from what He has created. Glory be to Him: He is Allah, the One, the Subduer (of all).
Had Allah wished to take to Himself a son, He could have chosen whom He pleased out of those whom He doth create: but Glory be to Him! (He is above such things.) He is Allah, the One, the Irresistible.
If Allah had willed to choose a son, He could have chosen what He would of that which He hath created. Be He Glorified! He is Allah, the One, the Absolute.