In the KJV, 1 Timothy 1:2 says:
Unto Timothy, my own son in the faith...
In the English translation in The Interlinear Bible (called "King James II Version") (TIB), however, it says:
to Timothy, a true child in the faith...
That's what the English words below the Greek text say as well. The word translated "a true" in TIB and "my own" in KJV is γνησίω (Strong's G1103).
In Strong's Greek dictionary, it says:
G1103 γνήσιος gnēsios from the same as G1077; legitimate (of birth), i.e. genuine:— own, sincerity, true.
Which translation is correct? A literal translation would seem to be "my legitimate son in the faith," but that would only make sense if Paul was Timothy's biological father.