Opps, I deleted my toddler! I accidentally deleted my toddler and now it won't respond to anyone and I can't select it to move it either. Is there a way to undo this or just make it start responding again?
If you deleted him; you should be able to save and when you enter the lot again he should be next to the mailbox all good to go....but I'm slightly confused since you said it won't respond to anyone and you can't select it to move it either...did you already save and exit and reload the lot? If that's the case; that happened to me once accidently. I came back and the toddler was by the mailbox, but acting like a baby stuck on it's back and the parents couldn't pick it up or do anything with it. I downloaded the insimenator which helped me out. There is an option to grow up to...I selected Child, as toddler wasn't an option on the menu. Once he was a child he was able to interact again...well that also put my toddler older than his twin brother who was still a toddler...so I choose the option to grow him down to toddler stage and things were fine. He has since aged normally; and I think he's a teen right now (I haven't played that house in a long time).
The insimenator has a whole lot of other functions too. I love it, it's a great help for my stories! I dunno what I did without it. If I were you, I would download the insimenator even if it doesn't fix your problem in the end (though I think it will, you'll be able to make the toddler selectable again like Shana said ). It's a brilliant hack.
Witch Baby can't play the game without it. It has an automatic refresh motives feature that's saved the life of many a sim. I even use it when the game does something stupid like make my vampires make their bed before going to work.