Mom with second stroke swallowing problems. went to the neurologist and doctor said its from lack of eating. ent saw them doc said infection from lack?

Infection with what?: Though lack of proper nutrition does increase the risk of infection because of decreased protection by thinned out skin/fat cushioning, wound healing , and an impaired immune system. However, if you are dealing with a diagnosis of pneumonia in a pt with swallowing problems, then aspiration (secretions/food going into the lungs rather than the stomach) is a major contributor to this diagnosis.

Swallow eval ; rehab: Your question doesn't seem complete but, in short, this person needs to be seen by an ENT who specializes in swallowing disorders and undergo a swallowing study. Depending on the results of that test and the physical exam, rehabilitative therapy with a speech pathology professional. It may not be possible to make things better but, you need to get the best advice available to find that out.