I have a lot of these pictures.
It's my beautiful partner Jen, holding a light meter and smiling for the camera while I check the accuracy of the lighting set up. Even though the smiling part is optional, she is typically smiling. Heck, even the part about helping me at a photo shoot in the first place is optional but she still does that too. She helps me lug and set up gear, she herds unruly kids and adults, she adjusts outfits and hair and lots of times reminds me about things I am liable to forget.
She does all this because she loves and support me and for that I am ever so grateful.