A parent trying to encourage a baby to say "Mama" by offering a treat, and the family dog wants in on the action:
Update: This video was made private for a while, possibly in an effort to discourage its being swiped by jerks. Downloading somebody else's videos and re-uploading them to a different YouTube channel is something talentless people do to try to get more subscribers.
(In case you're wondering if I'm guilty of something similar here, I assure you I'm not. I make an effort to embed the original video whenever I can figure out where it is, not a re-upload. The original YouTube Channel can disable embedding, but usually an embedded video benefits the video's legitimate owner by increasing the number of people who see it — along with any pre-roll or superimposed ads, which brings them a little income — and people who like the video can click through to subscribe to the channel. Other video sites, such as news organizations and Comedy Central, typically authorized embedding as well for similar reasons.)
It has since been made public again, but in case it's again made unavailable, what it shows is a baby being coaxed to say "Mama" by offer of a spoonful of food, while a very earnest-looking dog standing next to the baby and wanting food a well woofs and eventually says, quite clearly, "Mama." The baby then takes umbrage at the dog's greater success and tries to push the dog away.