Hephaestion

Hephaestion , son of Amyntor, was a Macedonian nobleman and a general in the army of Alexander the Great. He was ...160by far the dearest of all the kings friends he had been brought up with Alexander and shared all his secrets. This friendship lasted throughout their lives, and was compared, by others as well as themselves, to that of Achilles and Patroclus.

Hephaestions exact age is not known. No concise biography has ever been written about him, likely stemming from the fact that he died before Alexander and none of those among Alexanders companions who survived him would have had a need to promote someone other than themselves. Many scholars cite Hephaestions age as being similar to Alexanders so it is fair to assume that he was born about 356160BC. He is said to have become a page in 343160BC, a role common to adolescent boys of the aristocratic class in Macedon. As a member of the court, he may have met Alexander around this time.

Source: Wikipedia