With respect, I think you will find that the end of Chapter Six is going to be far more useful to you in terms of referring to the change in relationships that occur between the Curtis brothers at the hospital before they return to their house. Chapter Seven gives us little information about any differences in the family dynamics, so I will respond to your question referring to Chapter Six.
The reason why the end of Chapter Six is so important to the novel overall is that Ponyboy is reunited with his two brothers, Darry and Sodapops, and he suddenly realises how much Darry does care for him when he sees that he is crying at having Ponyboy back safe and sound. Ponyboy had always thought that Darry didn't love him because he shouted at Ponyboy all the time:
I let go of Soda and stood there fro a minute. Darry didn't like me... he had driven me away that night... he had hit me... Darry hollered at me all the time... he didn't give a hang about me... Suddenly I realised, horrified, that Darry was crying. He didn't make a sound, but tears were running down his cheeks.
Seeing Darry doing something that he hadn't even done at their parents funeral makes Ponyboy realise how deeply Darry does care for him and that every time he shouts at Ponyboy he is expressing his fear at something happening to him. This is the major change in the family dynamics among the Curtis brothers.