Friend in need of food and assistance?

She is a widow and has raised 2 sons, who are both grown. Both sons have steady jobs but take advantage of their mother. She had been working steadily as a substitute teacher but recently has had to take a job because her hours were cut.

Her oldest son bought 2 dogs and left them with her to take care of. Her youngest son is a Marine and is borrowing money from her to pay his cell phone bill.

She is very private and does not want to ask for help from people.

I understand that she has let her sons take advantage of her. I understand that she has let them walk all over her.

I have known her sons since they were very small. We are not close but we have know each other a long time; my husband and I were friends with the father before he died of cancer. And we live around the block from each other so we would see each other often going to school and driving in the area.

My question:

Should I approach the son about his mother? Part of me would like to lay into him for taking advantage of his mom. The other part wants to remain calm and reason with him.

Do I intervene?