Bucky is an Avenger, steve saved him from hydra. Steve also saved Jax, Bucky's wife since the 40's. Bucky and Jax were at hydra, Steve saved them both.

Bucky and Jax are both Avengers, still married and love each other. Jax has alpine, but no one knows, alpine is Bucky's cat from the 40's.

Bucky walked into their shared room, but sees Jax talking to alpine. He knew Jax could understand animals, but he didn't know alpine was still alive.