Because I exercise, I probably know that all human sports need muscle support. Smiling is also the result of muscles driving facial bones.

If muscles can't drive bones, not only can't you laugh, but other expressions can't be made. If you can make other expressions, your bones and muscles should be fine.

If it's not the bones and muscles, I don't know if you don't want to laugh at all. For example, I didn't think it was funny when I took pictures, but when I was asked to "laugh", I felt that the smile I squeezed out was worse than crying.