Autocapture User info

I have a workbook used by several people. Presently, the following code captures date, time and user name of the last person who changed anything.

Private Sub Workbook_SheetChange(ByVal Sh As Object, ByVal Target As Excel.Range)
Application.EnableEvents = False

For Each Sh In Sheets
If Sh.Name = "Br23" Then
Sh.[K2] = Date
Sh.[M2] = Time + 0.0833333333333 'prints Texas time
Sh.[O2] = UserLoggedIn
End If
Next Sh
Application.EnableEvents = True
End Sub

There is usually one line added every workday. I want to retain the above but is there a simple trick to capture the user name of the last one who made changes to any specific line and plug it into Col Q of that line? Example: Joe made entries to line 101 so Joe would appear in Q101. Tom made entries to line 102 so Tom would appear in Q102 (Joe still appears in Q101).