Ok.
So porter has a kid at 18. She's killed when he's around 35ish. That puts the kid at 17ish. The kid that was killed looked to be about 11ish.
????
"Oh. My. God...Batman and Obi-wan are having sex with each other." - Me, watching "Velvet Goldmine"
Based on the dates he gave under hypnosis, the daughter was about 10 when she and the wife were killed. I think the date of the tragedy was July 26, 1996. It was 1985 when his girlfriend got pregnant.
It also seems as though there was about 5 years from when Robert Porter was presumed dead and Prot is found at the train station.
JP