The best revision for this sentence is "Happily, my sister and I packed for a camping trip while our dad was at the store."
The original sentence places stars with the subject "my sister and I" (people acting) rather than with an adverb (a word that describes how the action occurs).
The best would be to move the adverb "happily" to the beginning as in "Happily, my sister and I packed for a camping trip while our dad was at the store."
Learn more about revised in: https://brainly.com/question/3238196
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