Photographing children is a challenge: they do the opposite of what you say and their movements are unpredictable. In capturing this photo, I've learned to think like my son. Instead of "hey look outside the window for this photo", I said, "Hey, look at that funny squirrel outside!".
For this photo, I made sure my main focus was on the reflection, using the bottom of the window as a leading line. Opened aperture to separate the reflection from the background. Photographed with Fujifilm X-T5 and Fujinon XF 56mm f/1.2 R WR.