We had a Baby Alive in the 70s (which was freakish enough that it ate baby food and pooped it out and heavens knows what happened in between)
What I recall happening in between was a grinding noise, which began when you put the spoon into her mouth. Grrrrmm, grrrrmm, grrrmmm as her robotic jaws gummed down the food. Then it would come out the other end the same horrifyingly bright color as it went in. I didn't have a Baby Alive, but some of my friends did, and I was horrified.
Circa 1980 there was Stretch Armstrong and a similar Incredible Hulk doll. They were very heavy and had arms that stretched in an ominous way, and that was the whole point of them, apparently. Kids I knew who had them seemed to use them mainly for bopping their siblings on the head, once the initial thrill of, "You can stretch his arms, woo hoo!" wore off. One day my dad took me to the home of his friend who had 3 boys who were supposed to entertain me while the dads worked on some project. We were quickly bored with Stretch Armstrong and began speculating on what was inside him that was so heavy and stretchy. The oldest boy got a butcher knife and murdered Stretch. He was filled with a strange gel that got all over the carpet. All the boys got spanked, but I was presumed innocent.