No. It's not appropriate. This type of topic involves very private and often embarrassing bodily functions. Writing about it in a fanfic can be seen as vulgar and disrespectful to others.
Well, you should have some cleaning supplies in the car like wet wipes and plastic bags. Use the wet wipes to clean her as much as possible and put the soiled items in the plastic bags. After that, you may need to take her to a proper place like a restroom to finish cleaning up thoroughly.
Well, this is a rather strange topic. But if we were to consider it in a non - inappropriate way, perhaps the 'desperate' part could mean she's in a situation where she's lost control due to some extreme circumstances like being trapped in a very difficult place for a long time without access to proper facilities. However, fanfics with such topics should be written with a lot of care to avoid being offensive or inappropriate.
Once upon a time, there was a little girl named Lily. She was still in the stage of wearing diapers. One day, she was playing happily in the living room. All of a sudden, she made a funny face and then pooped in her diaper. Her mother smelled it right away and quickly took her to the changing table to clean her up and put on a fresh diaper.
Once upon a time, there was a little girl. She was just a baby and couldn't control her bowel movements yet. One day, while she was playing in her crib, she suddenly pooped in her diaper. Her mother smelled it and quickly came to change her diaper. The mother gently cleaned the girl and put on a fresh diaper. And the girl just giggled throughout the whole process as if she didn't know what had happened.
One reason could be that she had a sudden and severe stomach illness. Maybe she ate something bad before getting in the car and couldn't hold it any longer. Another possibility is that she was too young to control her bowel movements properly and there was no toilet available in time while in the car.
I'm not really sure specifically what that exact story is about as it could be a very strange or made - up scenario. It might be some sort of fictional or even a shock - value type of anecdote that involves a girl having an accident while wearing a fursuit.
Once there was a little girl named Lily. She was out playing in the park all day. She drank a lot of juice and ate some fruits. As the day went on, she started feeling a strange pressure in her tummy. But she was having so much fun that she ignored it. Eventually, she couldn't hold it anymore and pooped in her diaper. She felt a bit embarrassed when she realized what had happened. Her mother quickly took her to the restroom to clean her up.
It might be due to a lack of access to a toilet in time. She could have been in a situation where there were no bathrooms around, like being in a long line outside a public restroom and not being able to hold it any longer.
A little girl was napping. When she woke up, she had pooped in her diaper. Her mom heard her fussing and came in. Mom saw the situation, quickly got a new diaper and some wipes. Mom changed her diaper while the girl babbled happily, not really understanding what was going on.