My sims

Ever since my sims have had a child, they have been very neglectful to their toddler. My adult sims will do their normal routines as if they don't have a toddler. My adult sims talk to each other, eat, and shower like normal, but whenever I click on their toddler, the command either disappears, or they pick up the toddler, and then put him back down. The only thing that they will do is bathe my toddler, but that's it. They won't feed the toddler, put the toddler to bed, let the toddler blow out their birthday candles, or pick up their toddler for longer than two seconds. My toddler's needs keep going down because of this, and I keep having to use the "Make Happy" cheat to keep him from getting taken away. I don't want any of my sims to die, and this is jeopardizing that. My Female Sim just recently had two other children (twins), and they do the same thing with them. It's kinda getting out of hand. I've tried restarting my game, I "Reset Object" all of my Sims, and it's still a problem. Can you help me? Thank you!