Well, it could be that the animal realizes it made a mistake and is showing remorse. Or perhaps it's part of a story where learning to say sorry is an important lesson. Another possibility is that it's just for comical effect to make the cartoon more interesting.
Maybe the animal did something wrong and wants to apologize. It could be a simple and common plot in a cartoon.
The cartoon girl might be saying sorry because she wasn't nice to a friend or because she failed to do something she was supposed to do.
Maybe the boy did something wrong and wants to make amends.
Not sure exactly. It might be saying something to warn others or to express its feelings about the place. Who knows?
Maybe it's because the storyline or the dialogue pace is not well-paced. It could make the cartoon seem sluggish.
Well, when a cute cartoon says sorry, it could have blushing cheeks and hold its hands together in a pleading way. Sometimes, they might have a thought bubble showing what they did wrong to explain their apology better.
It might mean the animal is leaving or saying goodbye. Maybe it's finished playing or moving on to a new place.
It could be that the characters are in situations where they need to apologize frequently, and'so sorry' is the way they do it. Or perhaps it's a cultural thing specific to the cartoons' storylines and settings.
Usually, a cartoon animal might have wide open eyes, a big grin, and maybe even a little hop or jump while saying hi. This makes them look super excited and friendly. Also, they might use some cute sounds like 'heeey' or 'hello there!'.
You might try looking on educational websites. Some of them offer printable materials like this for free.
The girl in the cartoon might be sorry because she didn't do something right or because she didn't meet her own expectations. It's all part of the story to add depth and emotion.