He didn't know at the time, but it's easy enough to figure out once Arthur starts showing up sporadically around town with his usually immaculate sense of time period-appropriate style slowly going out the window, that there might be some trouble in paradise. Bucky didn't exactly snoop, per se, but he's more or less confirmed that Arthur is now flying solo, blind, and he's pretty sure that wasn't the case before even though he never really got to know Helly all that well.

Didn't think that the town would have saddled him with a kid though. That's new.

Bucky shows up at Arthur's doorstep, bringing a bag with a big foil tray of enough lasagna to last the both of them a week but under the guise of having unintentionally missed book club and looking to catch up on what he might have missed out on. He can't knock with his hand full so he has to kick gently at the door repeatedly to give Arthur some auditory cues.

"Uh. It's me, Bucky." He's not used to having to announce his arrival but even an old dog can learn a new trick or two if he's given enough patience and training.