Might depend on Wes' taste in celebrations. I know very little about Wes apart from his connection with Owen and other co-writers. Wish I did know more.
Did Owen do anything for his 40th? I think he may have been in Maui but, other than that, I don't remember his birthday being reported much in the fan media. It was probably a private celebration involving only family and close friends.
Well according to twitter reports Owen and Luke have been in Austin the last couple of days, and as of now are out partying, so maybe they're with Wes as he's from Texas too, or could be his party is tonight.