Sentence:  A somewhat less fragmented hebephrenic patient of mine , who used to often seclude herself in her room , often sounded through the closed door - as I would find on passing by , between our sessions - for all the world like two persons , a scolding mother and a defensive <WSD>child</WSD> . 
Meaning of the word marked with <WSD> tags:  a human offspring (son or daughter) of any age