Grandchildren

I need advice, my two great grandchildren 3 n 4 are such lovely boys, but it’s actually getting me down in so much I don’t want to be here anymore, there father has been in prison nearly four yrs he does love them very much so they have all the best clothes which his family buy,but my granddaughter never has interacted with them, I have done everything I can to help with her flat, new tv, new three piece I would give her anything, I have them once a fortnite so she can go out, but recently she has started leaving them on a nite with random people,so she can stay out with some one she’s met, if there dad finds out and he will ime so scared what’s going to happen, I no it’s hard when you have no partner, but she gets lots of help, I feel so sorry for the boys, they only seem to eat pasta, it’s breaking my heart it really is, they get lovely toys from all the family but they only see them for a day n then they are put away in the bedroom, it’s so sad it’s no good me saying anything to her she will get angry n stop me seeing them, I have even thought about reporting her but that seems a terrible thing and what if they take them away that would just fin me, please help