Mother in law thinks my daughter has Autism

I’m furious. First of all - I was dating/engaged to her son since high school. We went to prom together,graduated together,and then had our daughter. She’s always been conceiving and putting things in my ex’s head. Next month we would’ve been together for 5 years. We broke up about a week ago because she fed into his head I should do EVERYTHING around the house including taking care of our daughter. He shouldn’t have to lift a little finger ever. I’m devastated we broke up - but now she’s saying my daughter has autism because she walks on her tippy toes,and is “always” whiny (she’s teething for Christ sake) and she’s only 18 months old. She doesn’t know how to deal with her emotions yet. She also plays on our front porch every day and when a car or a person walks by she runs and hides...she doesn’t like loud noises. Is she crazy or right? I’m going nuts.