Westwood, captain at Crewe before his move to Villa, is a big fan of Vlaar.
He told Villa's website: "Ron is great to have around the place. He's a leader, on and off the pitch.
"On the pitch he's a rock at the back. Whenever he plays he helps the team. He's always talking to the players and encouraging them on.
"He has a chat with you one-on-one too during the week. It's great to see him taking an interest in the other players, checking their mood and what's on their mind.
"He comes in on his days off too. I don't know when he has time to sleep because he's always at the training ground. He's so professional. That shows his commitment."