This was inspired by the time-travelling children thread in the challenges board. The basic premise is that Shirou's future sons & daughters (via different mothers) are accidentally sent back to the past, to the 5th Grail War, through a magical mishap or through Zelretch.
The children could also be from alternate universes (such as Shiro summoning - and having a child with - Caster). How would the children react to seeing their younger parents (the reactions of Saber's child and Rin's child, etc), the reactions of their mothers and father, and the reactions of the children to each other (after all, they have different mothers.)?
And, just for the sheer crack, one of them (probably Ilya's daughter) has a mild Electra complex.
The children could also be from alternate universes (such as Shiro summoning - and having a child with - Caster). How would the children react to seeing their younger parents (the reactions of Saber's child and Rin's child, etc), the reactions of their mothers and father, and the reactions of the children to each other (after all, they have different mothers.)?
And, just for the sheer crack, one of them (probably Ilya's daughter) has a mild Electra complex.