Weighing in

Whitey appears to have leveled off, at 13 lbs 11.5 oz. Billy gained another ounce. At 15 lbs 1/2 oz he's back near his maximum weight.

Whitey is also eating his food more promptly, which gives Billy fewer chances to raid it. We'll see if that does the trick, but I expect we will want to cut back on portion sizes, too.