Milk Drink is from Gen 2 (so still a GB/GBC game).

Did your brain successfully deleted all the memories from that godforsaken evil cow?

Although I can't find an instance of it happening in the manga or anime, in-game Milk Drink is mechanically the same as Softboiled, therefore, whoever's capable of learning that move drinks their own milk and spare some milk for thosein need.

Male Gogoats are also able to learn Milk Drink (egg move, probably).