Under https://github.com/BehaviorTree/btcpp_website/blob/master/docs/nodes-library/SequenceNode.md#sequencewithmemory you mention _On the other hand, isBatteryOK must be checked at every tick, for this reason its parent must be a ReactiveSequence._ but neither _isBatteryOK_ not _ReactiveSequence_ is part of the diagram.