In the beginning of episode 1 of Digimon Tri, we see glimpses of the second generation Digi-destined (Davis, Yolei, Cody and Ken; sorry I only know their English dubbed names) being destroyed by what looks like Alphamon.

Hikari and Takeru are technically also 2nd generation Digi-destined, so why weren't they with Davis and the rest when they confronted Alphamon?