iMessage added and deleting Group Chat Members like a ghost

Twice now on my family group chat.. one of the members appears to delete someone... and then add them back in or not.. and then delete someone else.. etc.. HOWEVER... these members of the group chat are NOT actually doing it... its like the iMessage takes over someone's contact for a minute and makes it seem like they are deleting or adding members of the group.. only the person isn't doing it... the "notes" from iMessage just suddenly appear on the text chain. "you have deleted (person's name) from this conversation"... The latest time that this happened (just tonight) I saw it happening and within 1 minute me and my daughter tried to add the members back into the conversation.. but it wouldn't let us... it took another 5 minutes or so before we were able to add them back in. This isn't the first time this has happened.. I saw on this apple forum that someone posted a similar situation CLEAR BACK IN 2016! and over 270 people had clicked on the "me too" and there was NO RESPONSE from APPLE or anyone else on this.. Have we been hacked? Or is this a glitch? APPLE?