I got WHEREOHWHEREHAS/MYLITTLEDOGGONE (17A: With 62-Across, question in a children's song) very quickly, but didn't see where he had gone until after I was all finished. He's scattered about between the two lines. SPOT, REX, ROVER, MAX, and am I right in thinking that SONIA and ELSIE could also be seen as theme material? Not everyone has male dogs, right?
I thought this a good, clean puzzle with a lot of good fill for a Monday. ROCOCO (15A: Elaborate architectural style), REGALE (27A: Entertain in a festive manner), PLENA (40A: Full political assemblies) - are these Monday words? And there seemed to be a lot of the more crosswordese-type fill, like OREM (34D: City near Provo), REATA (27D: Rodeo rope), and the ubiquitous ELAL (55D: Airline to Israel). I don't include CLU (24D: Gulager of "The Last Picture Show") because I've never, ever heard of him or her.
But I still thought it was decent. It's Monday, after all, and it pushed back a little, at least. I also appreciate the nod to my current illness with ACHOO (9D: Sneezer's sound). That was a nice, touch, and I'm touched, but now it's time to go rest again.