Where's my big baby gone?

As I waited for my coffee to percolate this morning, I saw the female baby blackbird being fed on the roof of the cabin with seed from the bird feeder hanging outside our backdoor. The parents are now quite used to coming up to the feeder to grab sunflowers seeds and suet pellets from the open tray, which makes it much easier for them to get the food, than the usual hanging feeders.

I went to get my camera but as I returned they both flew away. I hing about and once my coffee was made I stood near the back door watching for their return. The male parent suddenly appeared on the roof again standing for ages with this small snail with a striped shell, which is quite a renowned local variety, and probably a delicacy to the blackbirds.

There was a period of calling but no response came and the parent hopped around the cabin roof, where i caught this image. It then its rather large young offspring flying p the garden and landing in the top branch of the rhus tree where it started squawking and demanding food and attention. The parent flew across to the top of the fence opposite the cabin and then flew down the garden to the rhus tree. 

The demanding offspring made a lot of noise and postured with flapping wings and a wide open beak until the parent managed to force the young one to grab the snail, which it didn't seem to know how to eat. I think ti was supposed to pull the flesh out of the shell which the parent was holding in its beak but it took manage and several changes of posture. Eventually the deed was done and they both flew back down the garden towards where they nest. 

I did photograph the final exchange but it was so far away that it wouldn't have been much of a blip, so the waiting parent must take centre stage. I was worried when i saw this picture that it only had one leg, but I checked my other pictures and it did have two, even though it chose a one-legged posture here.