Melbourne, Australia - Mustard the dog and his Golden Retriever brother Honey recently got a new human sister. As a hilarious video shows, they've started training her early!

Baby Mackenzie was born and has been getting most of everyone's attention ever since.

Fortunately, this was not a problem for Mustard, as the dog quickly realized that the little girl could soon be of use to him.

Now that Mackenzie can almost sit up on her own, the Golden Retriever also expects her to perform the duties of a human.

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In a video posted by the child's mother and owner of the two dogs on TikTok, you can see Mustard walking purposefully to Mackenzie, who has been placed on the couch.

"How Mustard positions himself when he wants a back scratch," reads the onscreen text.

Without hesitation, the pup sits close to the tiny baby's lap and turns his back to her expectantly.

Mackenzie, who still has to learn what this means, looks a little puzzled in the first few seconds of the clip.

The baby's curiosity eventually works in Mustard's favor, however, as the little girl begins to explore the dog's back and digs her hand into his fur.

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So, without saying it, Mustard has achieved everything he wanted – even if he disappears shortly afterward and settles down in another spot on the sofa.

Apparently, the baby's tentative attempts to pet him were not quite satisfying enough.

"Mustard is training the little human young," jokes the child's mother in the video caption.