User blog comment:SayuriDarling/The Mark of Athena Official Discussion/@comment-5774152-20121214044606/@comment-5774152-20121214220807

I don't think she chose them out of spite. Because in The Son of Neptune somebody said (can't remember who) to Percy that Gaea hates him above all others except maybe for that upstart Jason Grace. So if it was out of spite then why wouldn't she pick Jason? Ephialtes said that Percy and Annabeth would most suitable for the task meaning she prefers them for a specific reason not just because she hates them.