Nicknames arise for various reasons. Some are shortened versions of given names - Elizabeth, for instance, can beget any number of wee names: Betty, Liz, Beth, Liza, Elsie. Others are reminiscent of sweet edibles - "Sugar," "Candy," "Muffin." And still others result from the naming of some personal trait - "Bright Eyes," "Whiskers," "Flash." Whatever the root, it is safe to say that the nicknamer - that is, the person who does the naming - reveals much about her/his true character when bestowing a name on another.
Which is why nicknames & pet names are a bit embarrassing to share sometimes. Nevertheless...
Elsie loves to nurse. When she was first born, she was all tummy, with the appropriate number of appendages spaced evenly on her little body - but that tummy was amazing. And she did her best to fill it. Now that she's on a roll, she's a pro, and we've got a good system down - sometimes I'll sneak out of bed early in the morning to get ready, and I'll hear her stirring, ready for her morning repast. When she sees me, she wiggles with glee, and promptly rolls over onto her side, arms stretched out and mouth open, in the ready position. Brilliant!
And so, not too long after her birth, Elsie was nursing (which is, of course, a baby's job - to eat!). She was wearing one of those little baby gowns, which are great for fast diaper changes in the middle of the night. Nathan comes in at some point to sat hello to his voraciously eating offspring, and picks her up, calling her, appropriately, a "Milk Sack." This impression, aided of course, by her apparel - a "Bag of Baby", it would seem.
Later, upon further reflection (and in reference to one of the favorite authors, J. R. R. Tolkien), this name was amended and redubbed "Sackville-Bagginses" who, if you are not familiar with the Tolkien stories, were of questionable character and always trying to mooch off of their more industrious and reputable relatives.
And then later again, upon even more reflection, this name prompted the name "Fatty Lumpkin," which was another Tolkien reference - Fatty Lumpkin was the big fat pony of Tom Bombadil. This one was my doing, I must admit, and I rather like it.
But the culmination I think, of this line of nicknaming came when Nathan, who was weaned, appropriately, on The Hobbit, reflected back on his dwarf names and recalled dear old Bombur, who was fat. Not only was Bombur fat, but he was only mentioned, it seems, by Tolkien in reference to his weight. He was "immensely fat and heavy" and loved his vittles: "To the food requests of the others, Bombur added pork-pie and salad." He "counted for two" and in later years had grown so fat it took six Dwarves to lift him. Brilliant again!
So now our dear sweet brown baby is called Bombur.
Although, I must say, there's a bit of difference in appearance between the two. Primarily the beard: