Can depression and sleep problems recur?

Hello doctor,

My mother is almost 50 years old. She is a patient with high blood pressure and cholesterol; sometimes, she gets fluids in her feet. In addition, she is taking medicines for related issues. Almost six years back, due to some issues, she got into depression and was unable to sleep for more than two consecutive hours for a month. We checked her check through a psychiatrist, and then within a month, the depression and issues with sleep faded away. She took medicine only for a month. But now, for a year, she has been facing sleep issues. Sometimes she takes the medicine for sleep (prescribed by her doctor dealing with B.P and cholesterol). But the pill sometimes works only. So, for the past three nights, she could hardly sleep properly.