An independent clause is a sentence or part of one that can stand alone.
So I have a feeling that the first one is correct as "My sister and I love to cook" and "we spend hours cooking together" can both stand alone yet are joined by a semicolon.
I hope this has helped
Often the difference is young adult novels have a more simplistic design than a classic novel.
An engaging thematic explanation of the poem
Gregor can't handle the furniture moving. He crawls out from behind the couch and globs onto the first thing he sees. It is a picture on the wall of a woman in furs. I think Gregor doesn't want to lose the possibility that he might become human again. The furniture reminds him of this.