About 20 years ago, I had a CNA babysitting me. One afternoon while I was sitting on the carpet playing, she put her hand to my forehead and said I felt warm. She asked if I had a baby thermometer, and I told her where it was. Next thing I knew, she had me lying on my back in my adult-sized crib. She took off my wet diaper and turned me on my side, then used Vaseline to gently 'prep' me for the thermometer, which was one of the old glass Mercury-filled types.
Once she'd inserted the thermometer, she began rotating it gently, which felt absolutely wonderful. I still remember that sensation!
Rectal temps became an occasional element of our babysitting sessions from then on. I absolutely loved those experiences.
Last year, I had a pediatric nurse babysit a few times. She took my temperature once, using a forehead thermometer, which wasn't nearly as much fun.