My Older Sister, Age 67, Has Lost 24lbs In 4

My older sister, age 67, has lost 24lbs in 4 months, loss of appetite, and now difficulty swallowing. We know she is depressed (recent due to her son/wife withholding contact with children). She has been pretty healthy, had a hx of ulcerative colitis, but has been under control for several years. She doesn't discuss issues much with 4 of us who are younger, has started discussing it more with her twin sister ( and son, both are P.A.'s). I should add her and her husband due drink slightly more than casual/social drinkers, mostly beer. Thank you, Susan (R.N.)