

The problem is the potential planet is so far that it would barely reflect any light. We have inferred from computer models that for known planet and object orbits in our neck of the woods, there needs to be a planet there to create those orbits.
We just can’t see it because it’s so far out there, it’s really really dark, and it doesn’t pass in front of a star to see the dimming effect that would let us know it’s there. If we knew where to exactly point telescopes, it’s possible with enough study we could say it’s really there.
In laws tell me to go to the park.