Hi, It may be because of adjustment issue. Or she may also have negative family history in her childhood or in her brought up. Talk to her parents and be get family discussion. And then go Marital Counseling with Counseling Psychologist , if he diagnosis her with any psychiatric illness then he may refer to psychiatrist. Usually talking therapy works well. I am sure your wife will take care of herself and kid well. She will be also good in behavior when you take her outside.

Hello,      Thanks for the query ,Extreme aggression,mood swings ,behavioral dusturbances ,might point towards a mental illness.visit a psychiatrist ,as a couple and follow up with the advice.

Consult any Psychiatrist directly or Online.