My 3 of my tamed horses and 2 cats despond.

I went into a ravine over 1000 blocks from my bed and stayed there for a little over 3 day/night cycles, when I came back it was night so I immediately went to bed and apon waking up i found that only the horse i took with me was there. i was confused and looked on my bed where my cats have been since I first got them and both were gone. vanished without a trace.