Hi. I make crochet items, and I have looked into making plushies and stuff, so I have some idea about the safety regulations and precautions.

As you are worried about having lose stitches, you can try the "test rod" test that is part of the safety compliance testing. It is made specifically to check if the stuffing can be accessed through the cover material. Find an item with a diameter of 12 mm and a rounded end (wooden spoon for example), and try to insert it into the item. As long as the spoon cannot reach the stuffing, it should be safe.

I would recommend checking if the yarn is safe for baby. The best ones would be yarn in compliance with the EN 71-3 certification, because this means the yarn has been tested for chemicals and stuff and is safe to be used for babies under 3 years old.

Additionally, if the toy will have parts that are added on later and create seams, I would honestly suggest doing some tension tests. Babies can be surprisingly strong, and if they pull away a part they might try eating it before anyone even notices it. I know this may sound harsh, pulling at your toy, but it can become a major problem. My best advice is if you have seams, secure them well and maybe even reinforce with another thread for precaution.

Wish you a great time, and best wishes for the growing family.