The use of "you're parents" instead of "your mother and father" is likely due to a grammatical error or a colloquial shortcut. In spoken language and informal writing, people often use contractions and abbreviations to simplify expressions. In this case, "you're" is a contraction of "you are."
When people say "you're parents," they might intend to convey the possessive form "your parents," but the contraction "you're" (you are) gets mistakenly used. This is an example of a common error that arises from the fast-paced nature of conversation or informal writing.
It's essential to be aware of grammar and proper language usage, but in casual settings, such errors can occur. To maintain clarity and correctness, it's better to use the appropriate possessive form "your parents" instead of the contraction "you're."