What you think about Allah?.Do you think that Allah has a family?. Do you think that Allah has taken to himself a Son?. Then what about the wive and other children of Allah. Do you think the same procedure for the birth of children as humans?. What you think if Allah has son or other children then they are also god. It means that you do not believe in one Allah.
Surely if Allah has son and other children then it means that one day the Allah will retire and his children will be god. Its foolish to think like that. Actually our thinking is very limited we guess the Allah on the human environment . We always try to bound the Allah between the limitation and boundaries. We forgot that Allah is above all and whatever is on the earth and heaven and between them are under the supervision of one Allah. All these things are not only under Him but also the obedient of Him. We forgot that Allah do not need the son. But it is the fact that Jews think that Hazrat Aziz is the son of Allah and Christian claim the same thing for Hazrat Isa. Due to this ambiguity in believe they will never feel the happiness as those feel who believe in one Allah.
Allah is almighty and above all the things. All the things are only under the supervision of one Allah. Kindly think that if there are two president in the state then a small government can not enforce the law in their own country. How is it possible that there are more then one Allah in the universe?. If we accept the concept of three gods as Christian then we are trying to limiting the powers of Allah and Allah will never be limited. Allah in the following verse of the Holy Quran mentioned this thing:
"And they say : Allah has taken to himself a son, Glory be to Him; rather, whatever is in the heavens and the earth is His; all are obedient to Him."
(Surah No: 2 & Verse No: 116)