I have a very snorey DH. I've tried every type of ear plug known to humanity.
The only ones that actually block out the snoring are Happy Ears but I wouldn't recommend them for a child as there's quite a knack to putting them in and they go well into the ear. That said, once they are in I can't feel them.
I've tried Loops and, by chance, used some again recently. They do go into the ear and fall out less than most (although I do wake up with them on the pillow sometimes) and they probably block sound slightly better than some, but they are very uncomfortable and wake me up with discomfort several times a night.
I'd say the pink and yellow Howard Leight type foam ear plugs are the most comfortable and block a certain amount of noise, but they fall out.
IME, all the other foam and wax ones are useless, uncomfortable, make my ears itch and fall out.