Junior is in love with your husband, the dance, whimpering, regurgitating and lowering of the wings is classic signs of a grey in heat, his hormones are active and he views him as his mate. You want to discourage this behavior as it only frustrates the bird. When he is like this do not pet him down the back, under the wings or anywhere around the tail area.
He has chosen your husband as his favorite person but the rest of the family should continue to interact with him, maybe they could be the ones to offer him treats and such.