   creator = useTracker ->
     displayUser message.creator
   , [message.creator]
-  children = useTracker ->
-    childrenLookup message
-  , [message]
+  children = useChildren message
   inner =
     <>
       {unless root

childrenLookup = (message) ->
  ## Lookup children in message.children, and annotate with extra fields
  ## `parent` and `index`.
  for childID, index in message.children
    child = Messages.findOne childID
    continue unless child?
    ## Use canSee to properly fake non-superuser mode.
    continue unless canSee child

  formattedBody = useTracker ->
    formatBody historified.format, historified.body
  , [historified.format, historified.body]
  children = useChildren message
  ref = useRefTooltip()

  onFold = (e) ->
