Unknown baby bird photos 2nd August 2020

I notice this baby bird on the 2nd August 2020 on a support of my caged cat walks. Some birds like it hot :o) I was only able to make a handful of photos with my Nikon. 5 of those were somewhat usable and they are the basis of the clip. The bird is almost exaktly 66 millimeters high and can fly, and thus will not grow so much any more. Who is a bird expert to tell me what a bird that might be. Please comment. I have an idea but i am not certain.

By now we now it is a robin. Thanks Kordula.

References:

Zur Technik: It is a series of photos done with a Nikon Camera. (6000x4000 Pixels) I cropped the pictures.