richpips you seem to know a lot about it being ok. Perhaps you would like to share your knowledge, rather than just rubbishing everyone elses comments?
Sorry to disappoint, my knowledge is no more scientific than the rest of the posters on the thread.
But if we presume a child has a shoe that fits with properly with a cleat in the correct position, which is then clipped into a SPD pedal that they can easily get out of. Then how the fact that they have “soft bones” “are still growing” has any bearing on them using SPDs alludes me.
Fell free to point me to some proper science that proves otherwise.