God Bless you for praying for her immediately! I was told from a child on that if you dream of someone, you should pray for them.
On another thread a few months ago, there was a topic about fearing death. I thought there were many good points. Sometimes dreams are a way of hashing out fears. Sometimes, I believe it is possible to get a little forewarning. Sometimes that forewarning is from a bad doctor’s report, or our subconscious picking up clues such as a person we see might suddenly not have ‘good color’ and yet we can’t quite put our finger on it.
And sometimes, maybe God permits us to know.
I also believe I’ve read here that if you are getting a forewarning about your death from the Lord, you won’t have to debate much what it is about. If that is truly what it was, meant for you, you’d have gotten that message loud and clear.
As a Christian, we are to always be prepared for Our Lord to take us home. Frequent confession, keeping the ‘end in mind’, is a good way to live.