Whom does the following describe? he is, in fact, but for his years and size, rather like a very impetuous baby "taking notice" eagerly and loudly, and requiring almost as much watching to keep him out of unintended mischief. his manner varies from genial bullying when he is in a good humor to stormy petulance when anything goes.

Describes Colonel Pickering who is a character in the play called "Pygmalion".

Explanation:

A florist who has a grotesque pronunciation in the eyes of an eminent phonetic becomes the experiment for a man who wants to prove that it is possible to make this poor girl a lady in the eyes of society, only by posture and the use of the English language. This is the story we know from the 1964 movie My Fair Lady with actress Audrey Hepburn. But it's not unheard of. It was based on play by playwright Bernard Shaw. And the name of the book is Pygmalion, written in 1913.

The play tells the story of Eliza Doolittle, a beggar who sells flowers through the dark streets of London in search of change. On one of these routine nights, Eliza meets a cultured phonetic teacher Henry Higgins and his incredible ability to find out a lot about people only through his accents. When he hears Eliza's horrible accent, he bets with his friend Colonel Hugh Pickering that he can turn a simple flower seller into a high-society lady in six months.

Colonel Hugh Pickering is described in the play as follows:  "He is, in fact, but for his years and size, rather like a very impetuous baby "taking notice" eagerly and loudly, and requiring almost as much watching to keep him out of unintended mischief. His manner varies from genial bullying when he is in a good humor to stormy petulance when anything goes."

you didnt put the link on, so i cant read the paraphrase