Did Kevan help kill his own grandfather?

[James Steller]

If you read the uncut passage on the Westerlands ( https://georgerrmartin.com/world-of-ice-and-fire-sample/ ), you'll see that Tytos Lannister once sent his father-in-law, Denys Marbrand, to bring the Tarbecks to heel after they forced several landholders out of their territory. Marbrand set off, but the Tarbecks were tipped off, so Lady Ellen's brother Roger Reyne ambushed and massacred Marbrand and his soldiers. 

Tytos ended up absolving Roger of guilt, because of course he did, but one reason that's speculated is the fact that Roger had Kevan Lannister as his squire, so Tytos might not have wished to risk his son's safety.

But that does make me wonder about Kevan's involvement with the men who murdered his grandfather. Was he there? Did Roger have to hide the truth from Kevan? He clearly served Roger for years, and Roger knighted him at the Stepstones. None of that seemed to matter when Kevan joined Tywin, of course, but it's the unspoken parts which puzzle and intrigue me. 

[Canon Claude]

It would explain why he’s so committed to Tywin. Not just relief that Tywin restored House Lannister’s reputation, but also the guilt over having served the men who killed his kinsman. I doubt Roger Reyne was stupid enough to bring Kevan to the ambush, though, especially since the whole point was that his brother claimed it was an accident. Kevan being there and seeing everything for himself would destroy that claim in a heartbeat.

[James Steller]

7 hours ago, Canon Claude said:

Kevan being there and seeing everything for himself would destroy that claim in a heartbeat.

Unless Kevan was deceived as well? And only found out afterwards?

[The hairy bear]

The extended version claims that "Archmaester Perestan has suggested that Lord Tytos may have pardoned Lord Reyne and his men because his own son Kevan was amongst them." I'd say that this confirms that Kevan was serving Lord Roger Reyne during the ambush.

Kevan was would be only 10 when the incident took place, so I'd guess that he would be easy enough to fool. And at that age, he is unlikely to have done much more than helping Roger into his armor. But in any case, it'd be very interesting to know more about Kevan's thoughts at the time he was serving the Reynes, and whether he considered the Red Lions his father figure or his captor.

[James Steller]

15 hours ago, The hairy bear said:

Kevan was would be only 10 when the incident took place, so I'd guess that he would be easy enough to fool. And at that age, he is unlikely to have done much more than helping Roger into his armor.

But he must have figured out what had happened at some point. And yet he seems to have stayed with House Reyne for several years, and Roger personally knighted him in the Stepstones. Not to mention he went on to ride alongside Tywin to destroy House Reyne once and for all, massacring everyone he must have grown up with. Did he feel conflicted? Did he feel nothing but satisfied vengeance? Either one would explain his devotion to Tywin, either to overcome his inner conflict and guilt, or out of devotion for restoring House Lannister's rep. Maybe a bit of both? It's a shame we didn't learn more about it from Kevan's POV.