Honda is recalling certain 2011-2017 Odyssey vehicles. The second row outboard seats can slide sideways to one of two positions. If a seat is placed between either of the two positions when attaching the seat to the floor, the seat will not latch properly to the seat striker, allowing the seat to tip forward unexpectedly during braking.
Honda has released the remedy to dealers. Until you obtain the factory remedy, when installing the seat make sure that it is latched in either position and not installed between the two positions.