Exegesis:

posos (cf. 6.38) ‘how long.’

chronos (cf. 2.19) ‘time.’

hōs ‘as,’ ‘when’: here it is a temporal conjunction meaning ‘since.’ The question asked by Jesus, literally translated, is: ‘How long a time is it since this (first) happened to him?’ (cf. Translator’s New Testament).

paidiothen (only here in the N.T.) ‘from childhood.’

Translation:

His father is ‘the father of the boy.’

The expression has … had this, though quite intelligible to us as English speaking persons, is not translatable literally into many other languages. These may require such renderings as ‘has he suffered this way,’ ‘has he been afflicted,’ or ‘has he had the demon in his heart.’

From childhood is an elliptical expression which may require different degrees of expansion in various languages, ‘he has suffered since he was a child’ or ‘even when a little child he suffered and still does.’

Quoted with permission from Bratcher, Robert G. and Nida, Eugene A. A Handbook on the Gospel of Mark. (UBS Handbook Series). New York: UBS, 1961. For this and other handbooks for translators see here .