The larger dream context was that I was hanging out at an airport bar waiting for a flight (so that my dream could ambush me with stress about missing that flight) and someone in the group of people I was with mentioned that they had been involved in the new meme.
It was a copypasta meme based on an anecdote that someone had written up on facebook, my memory is that the meme looked like a screenshot of the post plus a couple of pictures that had been included.
The anecdote was about a woman who took her two children (boy 11/12 and girl 8) to the cinema. The girl was a huge fan of sheep, and as they were queueing for drinks and tickets she struck up a conversation with a man in line behind them (the man was the one at the airport with me). Then the man... Took??? Kidnapped??? The girl, but not to do anything bad. Instead, when the woman and her son went up the escalator in the cinema, they saw the man and the girl waiting at the top, both of them wearing inflatable sheep costumes. The attached picture was of this moment, a short man and an eight year old wearing these absurd outfits in a cinema lobby.
It's crucial to this that the tone of the anecdote wasn't scary or horrified but comical, like this was a whimsical and cute thing that had happened sort of incidentally. Although in the dream I did think the guy was a bit of a weirdo.
(he had long white hair and a black pencil moustache and was short and about 20 years old and I think his name was ambrosius, make that make sense)
Anyway there you go, meme of the century: copypasta anecdote with inflatable sheep costume picture.