Student or Learner
I remembered Sabina's saying that Old Nanny Tester went off into "funny fits," and her chatter about the old woman had been so interspersed with other matters—in Sabina's habitual manner—that I had not really taken a great deal of notice, because there was so much at Giza House to concern me. I had seen Nanny Tester on one or two occasions and had thought her a peculiar old woman, but as there was so much that was strange in Giza House, she did not seem so unusual as she would have elsewhere.
went off into "funny fits" ?
'Fit' as in a period of behaving in a particular way (not a 'foaming at the mouth' sort of 'fit'). And 'funny peculiar not funny ha-ha' - as we commonly say to distinguish the two sorts of 'funny'.