Penny Lancaster, Brooklyn and Nicola Peltz-Beckham, Susanna Reid, Piers Morgan, and Romeo Beckham were among the famous faces who liked the post in a show of support.
Mr Gerber, born on July 2, 1999, died on September 20 at a rehabilitation facility in Santa Monica, California, according to records from the Los Angeles County Medical Examiner.
The Los Angeles Times reported that emergency services were called to the centre following reports of a possible overdose and cardiac arrest.
Santa Monica police launched an investigation into his death as a suspected overdose, stating there was no suggestion of foul play.