These approaches generally homogenize characters and simplify their personalities. It hasn't died out, alas, as Baby Looney Tunes attests. It can become even weirder, however, when the characters in question have already been stripped of most or all of their gumption, as with Mickey Mouse in the 1980s, when the "Disney Babies" first surfaced. They still appear on and off, and serve only to fulfill a "Look how cute" function, in a world where the Disney Babies (actually called that in one book) have no discernible personalities whatsoever outside of being cute and nice and emotionally fragile.
And this was worse when they went beyond Mickey, Minnie, Goofy, et., in search of more characters. To wit, gaze at the image below:

At least Baby Horace retained his collar (this book, picked up for sixty cents, has Horace missing his blanket, but he's quickly comforted when his newfound daycare pals let him use the daycare's teddy bear. The end.) While revivals of Horace and Clarabelle are generally a good thing, this is just sad.
Moments ago, I took a closer look at the endpapers, however, and found this, which is even worse:

No doubt somewhere out there, they also have an infant Phantom Blot (the shy Blotty, who feels self-conscious because he looks different) or a Baby Scrooge (Booge?) who likes money only because it's shiny. Sheesh. (This is still less disturbing than that Baby Popeye image that circulated awhile back, though, with a teeny tiny Baby Baby Swea'pea hung around Baby Olive's neck).