Leaving work to care for disabled child

Hello, just hoping for a few answers/other people's experience....

My partner works full time, and I work 16 hours a week. Currently receive CTC for my 2 children. My son is autistic and my daughter is currently going through eating disorders and related anxiety/depression. I am missing more and more of work due to school meetings and hospital appointments for both children, therapy sessions for my son, both in home and at clinics. As a result of this I'm feeling very stressed and pulled in so many directions, I feel I need to stop work for a short while until both kiddies are back on track, perhaps until the next school year starts.

Would my leaving work affect our current CTC claim, i.e. Would the claim stop for a while because I left work of my own choice, or would the claim adjust when I inform them of change of circumstance (similar to telling them of increase/decrease of hours)?

Many thanks in advance.