Trajectory and the ouchy elbow.

I was watching them do schemas in the bath. Hazel was spraying the bubbles up into the air with a plastic fork. Iris was coating herself with them. Suddenly Iris started crying. I crouched down and asked "What happened Iris?"
In tones of deep tragedy "My elbow ouchy," she replied.
"Oh, did it bump on the side of the bath?"
"No, Hazel fork."
"Oh. You poor thing. Is it okay now?"
"No." still very sadly.
"Hazel, I think you should talk to Iris about her elbow."
Hazel, who had been carrying on in obliviously deep concentration sighed and turned to Iris to ask
"Iris, how does your elbow feel?"
"It hurt."
"What kind of hurt, is it bleeding kind of hurt?"
"No. Bubbles kind."
"Can I see it?" she asked with interest.
"Okay." Iris showed her the elbow, it was definitely the bubbles kind of elbow and so may well have been suffering the bubbles kind of pain.
"Does it need a kiss?" she asked very kindly
"No! Not you kiss my ouchy elbow!" Iris spit back vehemently.
"Oh," Hazel, a little rebuffed, to aid her thought processes, flicked the bubbles gently, "does it need a kiss from your Mummy?"
"No..." Iris raised a smiling face to her, "I fine."