Just FYI for any dog owners, young dog on left appears to be legit stressed out here and maybe should be comforted or removed from that situation before something goes wrong.
Recognizable cues include side eye with prominent sclera, pulled-back ears, avoidance posture with minimal head rotation and muzzle tension at mouth corners. Those not apparent here include tail-tucking, lip-licking, and yawning. Your dog broadcasts its internal state with cues like these, so it helps to know them.
Edit: and sorry for being a buzzkill, it’s a funny photo