God the weir !!!!

On my way home from walk I came across the duck family heading straight into the weir, Mum made a couple of attempts to get up on top leaving small ones getting pounded by the water. Mum then took small ones to the side then made a successful attempt. On seeing this the small ones came back out just to get pounded again this time they retreated back to safety. Took some photos good and not so, had to leave so don't know outcome. But what was not right, yesterday Mum had 7 ducklings could only count 6, hope 7th is with Dad?