Sometimes when people make maps of Australia, they forget to draw an island called Tasmania. Tasmania is a small island located next to Australia, and even though it is a very important part of Australia, people sometimes forget to include it in maps.
It's kind of like drawing a picture of your family, but you forget to include your little sister or brother. Even though they're small, they're still an important part of your family, and it's not fair to leave them out. The same goes for Tasmania - even though it's small, it's an important part of Australia, and it shouldn't be left out of maps.
It's not really anyone's fault, though. Sometimes cartographers (the people who make maps) have to fit a lot of information onto one sheet of paper, and Tasmania might not fit easily. Other times, they might simply forget to include it. But it's important for everyone to remember that Tasmania is part of Australia, and it deserves to be represented on maps.