Obey Zolac!

Those pictures are just the ones that come with the frame! At some point in the future Amy and her baby are gloriously reunited and someone snaps a picture and as it passes through time some sod in marketing somewhere gets a hold of it and goes "Oh, this is a happy moment, it will make people buy this frame!" Plot point solved! (What I'm really trying to say is this is the kind of thing that happens when Moffat gets it into his head to make everything all twisty.)

The more I think about it, the more zolac_no_miko seems right on the crossing timestreams thing (timestreams, timerivers, timeponds?). The Doctor and Rose were fine crossing their own timelines until Rose touched her past self. So, non-interference with your past self is key (though minor interference in past events is okay. So I guess River involved in saving her babyself would've been not okay, but if she were to be involved in the kidnapping (which happens anyway), it might be okay? I dunno...) It seems like it makes sense for River not to cross her own timestream (and Rory does point out that last time the Doctor did it, the universe blew up), but she's also markedly absent (I think) from all the scenes with the girl, other than the mysterious lakestronaut scene... how involved in the events around your past do you need to be before it counts as interfering? (Because what's the point of time travel if you can't be in two places at the same time?) I think I'm just rambling here now, so I should probably stop.