...at the same time, without knowing about each other's plans, one of them came to see her daughter who lives here, the other came here just for fun, and they both want to meet me. But I just learned that they are not on good terms with each other. It is a problem.

It is not my fault that they came here at the same time, and they are not on friendly terms. I don't understand why siblings just cannot live in peace.

(I have three nieces, the middle niece is not coming here now, the one I've had the most contact with.)