they do this all the time. they're laying on the shelf i built when I put my A/C unit in the window. Usually wilbur lays down, and tinker comes over and starts cleaning his head, and sooner or later she just fades away
What a precious picture. To you they are the cutest in the world, and that is all that matters. They are pretty darn cute by anyone's standards though!
PS seeing that Red Boy from that particular angle and position gave me a shock, as just from that bit of him, he could be my Tolly! Tolly is the sweetest Red Boy on my Earth and often offers his head for kisses and head bumps, just like that..