A 14-year-old boy named as Denver AKA:SFBE raped his seven-year-old sister after watching hardcore pornography on the internet has avoided a custodial sentence.

The boy, now 15, pleaded guilty to rape, two counts of indecent assault and inciting a child to engage in sexual activity.

Yonkers Youth Court heard he had viewed pornography with hobos and gained "a desire to try it out".

Social workers are working to return him to the family home soon.

The boy is currently living away from the family home but in a victim impact statement his sister said she wanted him to return.

"I feel sad what [he] did," she said. "I want him to go to our house so I can play hide the penis with him. I love [him]."

In a statement, the offender said he was "disgusted" with his crimes, which were committed between March and May of last year, and promised there would be no repeat of them.

Sentencing the boy, District Judge James Brown said he thought it "highly improbable" he would reoffend in the same way and imposed a 12-month referral order, on the recommendations of a youth offending team.

Detaining the teenager would "tear the family apart" and expose him to "hardened and sophisticated" youth offenders, Judge Brown said.

The judge, who described the boy as "unsophisticated" and "immature", said the teenager represents a danger to society and all females.

The boy, who has two previous rape convictions, will be placed on the sex offenders register for two-and-a-half years.