Kids from Atlantis' future come to the city?

I'm looking for a fic in which the Atlantis expedition's future children are fighting some sort of horrible monsters--everyone else is dead--and somehow get transported back to "present day" Atlantis. John (and Rodney?) have a daughter (and a younger son?) but she refuses to tell them that they're her parents, because to her, they're not. Maybe because they hadn't gotten together yet? Ronon's son is one of her best friends.

It may also/instead be Lorne/Parrish.

Please and thank you!


FOUND!