This is personification because:
* Pigs cannot speak. Charlotte is giving Wilbur a human quality by attributing speech to him.
* "Some pig" is a human expression of admiration. Charlotte is using this phrase to express her fondness for Wilbur, but pigs wouldn't use such a phrase.
This is just one example, and there are many other instances of personification throughout the book. Charlotte often uses human-like language and thoughts to express her feelings and actions, which makes her character more relatable and endearing.