The analyses of a text #3

The narrator recalls his childhood; he is now in custody by his stepfather in his room.
He had been living with his mother [Clara], Peggotty the only maid of his house, his very stern stepfather Mr. Murdstone [Edward], and Mr. Mudstone's eccentric elder sister Miss Mudstone [Jane] in his late father's house when he was forced to go to Salem House, the boarding school near London.
Now he came home after the stay at Salem House during a semester.
.......................
My mother's lips moved, as if she answered "Yes, my dear Edward,"
"I was sorry, David, I remarked," said Mr. Murdstone, turning his head and hes eyes stiffly towards me, "to observe that you are of sullen disposition. This is not a character that I can suffer to develop itself beneath my eyes without an effort at improvement. You must endeavour, sir, to change it. We must endaevour to change it for you."
[David Copperfield by Charles Dickens]
I'd like to know "I was sorry~" is an object of "remarked."
I'd like to know if "a character" is an object "suffer" and "to develop" means "it develops."
Thank you in advance for your help.