Nà yī kè, bēixǐ jiāojiā, tā bù zhī gāi kū háishi xiào.
At that moment, grief and joy intermingled, and she didn't know whether to cry or laugh.
Tips
usage
交加 almost always appears after a paired noun phrase describing two simultaneous forces or emotions: 雷电交加 (thunder and lightning together), 悲喜交加 (grief and joy mixed), 饥寒交加 (hungry and cold at once).