Explaining death to a toddler

My ex mother in law passed away over the weekend. They found the cancer about a year ago. This is my 4 year olds mawmaw and he is very attached to her. I did not have a good relationship with her but she was good to my baby and that’s what matters.

My question is.. how can I explain to my son his mawmaw is gone now without hurting him or confusing him. I’ve done some research online and found some really good points as far as things NOT to say.. but I’d like to hear some real stories.

My baby is heartbroken. And is asking questions I should have prepared myself for sooner.

Any help is appreciated.