My grandpas cat just died

I just found out my grandpas cat just died I don't know when because my mom never tried to tell me until today because I guess she didn't think it was important or maybe she just didn't want to make me and my sister sad idk? But anyway I just feel so sad and depressed now because even if I didn't see the cat a lot I still really liked the cat and it was only 1 year old at most and it didn't even die in peace apparently it died due to it eating rat poisoning idk if that's painful way for cats to die but I doubt it's a good way to go and it's even more depressing bc I remember being able to feel it's heart beat when I had hold him because he was so small and I know it's not my cat and I shouldn't be this sad and depressed about it but I just can't help it now I just don't feel like talking to anybody or even do anything anyway this post didn't really have any real meaning I just wanted to let this out