Should I capitalize a word from the middle of a quote if the quote and word occur at the start of the sentence?

I was writing an essay for a school assignment, when I encountered a quote similar the following:

Nobody has encountered a black hole, because they’re simply too far away to reach.

I then needed to write a sentence like the following:

"they’re simply too far to reach" refers to how black holes are tens of thousands of light-years away at the nearest.

I then wondered if "they’re" should be capitalized to say "They’re" instead, because it’s the first word in that sentence. Should it?