Embryo adoption is when another family gives a tiny, tiny baby (called an embryo) to another family who wants to have a baby but is having trouble doing so on their own. The embryo is really, really small - it's like a few cells all bunched together. It's so small that you need a big microscope just to see it.
The new family takes the tiny embryo and puts it in the mommy's belly so it can grow into a baby just like a regular pregnancy. Sometimes, the mommy will need to take special medicine to help her body get ready to take care of the baby.
After the baby is born, he or she is just like any other baby - they like to play, eat, and learn new things. And both families are happy because the first family knows that their embryo became a baby and the second family has a new addition to their family. It's like a big circle of love!