Character jumping on a ship

Hello,
I have a ship that moves and sways on waves, and I also have a character. While character is on the ship, it becomes a child of the ship, which allows it to stay on and move along with the ship’s swaying and movement on the waves. However, I encounter a problem when the character jumps. Even when it jumps, character still follows the ship’s swaying and movement caused by the waves while in the air. If I remove the character from being the ship’s child when it jumps, the character flies backward because the ship is moving. Does anyone have any suggestions on how to solve this?
Jumping

Well, one way I would use is not to make it a child, never.
Let’s say that the vertical velocity is in the ‘y’ axis, while the person is on the ship, its position follows the position of the ship.
Once it jumps, its initial vx and vz is that of the ship, and gradually it diminishes, so if it jumps high enough, he will fall on another part of the ship (or outside of it).

But I want the character to land in the same position it jumped from, as if jumping on a bus

I agree with chclau1. There isn’t really any reason to make the character a child of the ship. The character should already have the ship’s velocity if standing on the ship and so when it jumps it will land at the same location it jumped from.

If the character is a character controller then you can add the ship’s velocity to the character so then it will move along with the ship without needing to be a child of the ship. If the ship is a rigidbody then you can get the velocity directly below the character with GetPointVelocity.

Here, the character is not a child of the ship. How can I solve the jittering problem?
Ship2

I don’t see any jittering in the video. If your character or ship is a rigidbody then enable interpolation. Or if the character is a character controller then make sure you’re updating its position in Update and not FixedUpdate.

Character characterconroller, ship rigidbody
But there is jittering while ship changing location and rotation on a waves