Hi, I tried to make the title as informative as possible.

I made the teen skirt long and when the sims sits the skirt is perpendicular to the spine and pops out through the legs and everything. (I can get a screenshot if needed)

I'm pretty sure there should be a tutorial explaining this, but I haven't found it. I would be extremely happy if someone could point me to one! (Or tell me how to fix this problem.)

I am using milkshape. To make the skirt i used neptuneSuzy's tutorial.
Thank you.

It is because of the vertex assignments - you can't simply grab the bottom of a skirt and pull it down, you have to take the vertex assignments into account.

To lengthen a skirt you will have to add vertices in the correct places where the skirt must bend with the legs, then properly assign and weight them.

The best thing to do when making a project like this is to start with a skirt that is as close as possible to the length you want, otherwise it becomes very difficult to make it animate correctly.

See the UniMesh thread, and the meshing articles in the InfoCenter for more information about this.

Thank you !
Well, I guess i'm going to start learning to assign and weighten verticles.

One thing I did right was i chose the longest possible teen skirt, the almost knee-length one. Anyways, I obviously have a long way to go so Thank You very much for answering!