That's a good question. As that was happening, I was wondering... is he recalling something that he had done to a child in the past, OR was he seeing THIS zombie as he was before he turned? I couldn't determine for sure if it was the same actor, with and without make-up or not.
There were definitely similarities.

 

I wasn't sure what to make of that scene either. Initially I assumed that he was remembering something that he'd done to another child in the past, but I'm not so sure now. It could have been something that happened to him in the past, but that seems unlikely to me. It seems fairly plausible that he was just envisioning this kid as the kid that he was before turning.

 

I was certain that in his role he had to kill a lot of kids or torture them for information, and putting down kids as walkers reminds him of that so it's bringing up his past and haunting him because he feels guilty for what he did to innocent kids .

 

All will be explained about the flashback in the next episode (per The Talking Dead).

 

The flashback was a little too vague to have much meaning or impact. I think they have too many people going crazy at once.

 

Nah... torturing kids would make him too unlikable a character. He may have orphaned some, but not tortured them.

Killing the zombie little girl affected Nick. He had time to SEE her, and decide... damn I have to put her down. Salazar with the alter boy, also had time to SEE him as an innocent little kid. He could hold him off, and decide. His daughter Ofelia on the other hand, saw her dad in danger, didn't have time to THINK... but only to REACT! As a result, she may not have issues. I hope not.

 

THIS (Bold added by me for emphasis). But, totally this. I was going to start a separate thread on it, in fact. Between Chris, Nick (believing, now, that the zombies are spiritual or anything besides needing to be killed), and Daniel, then toss in Celia for good measure, there are just too many people going crazy at this point. I mean, in a sense that's actually believable in that if the apocalypse were actually among us, we'd likely have people losing their sanity who otherwise wouldn't ...but it's a fictional show and this just isn't helping the plot. One token crazy person? Okay. Two? Well, I'll deal with it. Three, four? WHY?

 

No. The actress who plays Ophelia just said the flashback would be explained in the next episode.