would they grow up normally or would these seemingly random symptoms get worse and worse?
typically they will get worse. there is no treatment for autism, it cannot be cured. instead there are therapies to help autistic individuals to adapt to normal society and to learn to cope with their differences.
Autism affects every child differently which is why it is called a "spectrum disorder". if your child is diagnosed with autism, early intervention is critical to gain maximum benefit from existing therapies and so that child can reach their fullest potential.
Depends on the severity of the Autism if they're highly functioning more then likely they'll be just fine. if they are more down the scale you're not going to be able to treat them normally. There are treatments, but they aren't very good, but some have shown improvements such as equine therapy.
there is only medicines to help people and childern cope but no real way to fully recover from autism best to seek medical help and see what they say in this situation is my best advice