Neglected mother-in-law

My mother in law is 90. My husband (her son) died and I have since re-married. We are close and I see her every week. She has one other son and a daughter. She has no relationship with the daughter who is a troublemaker. Her husband has also passed away. My problem is that the son lives an hour away (I live closer) but rarely visits his mother. She stayed for 2 nights over Christmas and I don't think she has seen him since. Neither of his children visit (they see her at Christmas when she stops over) She lives in sheltered housing so is well enough looked after but I think she is lonely and misses her family. One of my sons who lives close also visits regularly and my other children visit when they're in the area (one's overseas and one over 3 hours away) This weekend she had a fall. She is slightly bruised and battered but incredibly shaken up and upset. I have been over and done some shopping for her but I feel something must be said to the son about not seeing his mother To be honest I don't know what to do or what to say. Frankly I am disgusted that he pays her so little attention and gives so little of his time. Is it my place to say anything or should I just butt out and keep doing what I think is right for her. I know this upsets her but she keeps making excuses for him: "he works so hard" "He is so busy" "He has his wife's (recently widowed Dad) to look after". I'm finding it increasingly difficult to hold my piece. Any advice please

Thanks for both your replies. Sensible advice yet again. I have wondered about her past relationship with her son. She and her husband moved around quite a bit with his job and the son stayed put once he was 18. My late husband was the youngest child and stayed with his parents - moving schools to suit them. His mum was very close to him and I wonder if the other son felt left out and not really part of the family. I have simply messaged him to say she had the fall and was shaken up and I will continue my relationship with her in the way I have always done. We enjoy each other's company. As long as I can come on here and vent my frustrations about my brother in law!!! Thanks friends

CHRISTY- I've been where you are. The advice you got here is excellent, and I wish I'd taken those sentiments closer to heart. I just wanted to add: Take your path of least regret, and make the choices you can live with. And let everyone else do the same. Whatever they choose now, they'll have to live with. Spend your time focusing on the relationship you have with her, and stop trying to make sense of how anyone else behaves. I watched as FIVE adult children- all within a couple hours' drive- ignored their mother for three years, while she was dying. It infuriated me. Until I remembered 1) it's none of my business how anyone else behaves, and 2) I could only make choices for myself. It wasn't easy, but I eventually worked my way through to gratitude. Their neglect gave me more time with her, and we got much closer than we would have otherwise. I was selfish in that regard. I know it hurt her a lot (she was living with us during treatment so I saw and heard her pain). I hate that, but there was nothing I could do about it. I could only control how I reacted to it. I could let it go and love her harder, or I could let my anger infect my time with her. So I let go of my anger, in favor of holding onto my mother-in-law's hand. I hope you can do the same. For your sake, and hers.