Mysterious Mr Gnome

The baby/toddler gnomes, grow into the one with the dungarees and a hat thats still too big, thats their child version, and the dark gnome the teen. I've never kept a household running long enough since the babies finally started appearing in my game to actually get to the teen point before. I swear they've changed something about how the gnomes work, because the babies seem to be much more common and I used to loose gnomes, I thought they just sort of wandered off because I'd not see them round the lot again, nor see their little golden gravestones.

Its so sad to see all those gnomes grow old and die :(

Is it only the mysterious gnome that can have babies and grow old? I've not noticed any of the others mutliply (except the vampire with the teddies)