A man who ended his birthday by beating up his mother and step-father has been jailed for four months.

Robert Dunlop-Miller, 20, went "berserk" after a drinking session and attacked his mother Sarah, 36, and her husband David Armstrong, 35, Lewes Crown Court heard.

He became involved in an argument with Mr Armstrong after the two men returned from an evening out.

During the ensuing fight, Dunlop-Miller attempted to bite off his step-father's ear and hit his mother.

He was only subdued when his mother hit him with a stool and his sister smashed a glass on his head.

Prosecutor Paul Rogers told the court that at the time of the incident in November, the four were living together in Marston Court, Hove.

Dunlop-Miller and Mr Armstrong went to a pub and club to celebrate his birthday before returning home in the early hours.

Mr Rogers said: "The defendant's mother had gone to bed and when her husband went upstairs she complained about the time of night.

"Mr Armstrong stated he had gone to the club to watch 'Billy' because he was concerned that when in drink, he became troublesome.

"The defendant burst into the bedroom and demanded Mr Armstrong go downstairs 'to sort this out'."

Dunlop-Miller was said to have pushed his mother out of the bedroom before trying to put her husband in a headlock.

Mr Rogers said: "At one stage, the defendant had Mr Armstrong's whole ear in his mouth. Mr Armstrong needed 12 stitches to repair the damage."

Mr Rogers said the violence only stopped after a glass was smashed over Dunlop-Miller's head by his sister.

Dunlop-Miller, who has previous convictions for criminal damage and motoring offences, admitted two counts of assault occasioning actualbodily harm.