Are taste buds different between an adult and a child?

Yes because they change in age just like you.

For instance, a child's sense of sweetness is less developed, and it takes more sugar to feel overwhelmed (and it seems more special. On the other hand, children are very sensitive to bitterness compared to adults, thus leading to their general dislike of Brussels Sprouts, and dark greens vegetables-- the bitter taste is so much stronger to a child.