A high court judge has used Twitter to urge a woman who disappeared with her three-year-old son six months ago to return home.

The child, Olly Sheridan, has been missing with his mother, Ellie Yarrow-Sanders, since last July.

Mr Justice Williams tweeted the appeal from the @JudiciaryUK account and included the hashtag #comehomeolly. It is thought to be the first time a judge has used Twitter in this way.

Williams said he was concerned that the child had been missing for so long, and said he promised to deal with the mother’s case fairly.

Last December, the judge waived an anonymity order in an attempt to try to find Olly. The child and his mother had disappeared a few weeks before she was due to give evidence in a custody hearing.

Patrick Sheridan, Olly’s father, has agreed not to ask for Ellie or her mother, Donna, or sister, Maddie, to be punished for taking any part in Olly’s disappearance if the child is returned before the next hearing. Ellie’s mother and sister support the judge’s appeal and are also urging Ellie to bring Olly back.

In a joint statement, Patrick, Donna and Maddie said: “We just want to know that Olly is safe and we plead for Ellie to return home as soon as possible. We all agree that Olly needs to come home to his normal life surrounded by family and friends.”

A senior social worker was appointed on the case to promote the Olly’s welfare, but the judge insisted it did not mean there was any chance of the child being placed in foster care.

Essex police have urged anyone with information to get in touch.