I have a severely disabled child.
I am also a lone parent (dad has been totally absent since day one)
I returned to work when my child was a few months old after mat leave. Had to give it up though as my mum was unable to care for my child. No other family could. And I couldn't afford specialist childcare on NMW (even with tax credit help).
I was on IS until my child was about two. I was bored and depressed being at home all the time. And i was soooooo poor. I didn't know anything about DLA and was buying all the specialist equipment from my benefits and through selling things.
I registered with HMRC when my child was two and started doing cleaning and ironing, taking my child with me. Still wasn't earning much but eventually I managed to come off IS.
When my child started school, I got phonecalls on a daily basis asking me to come in as the teachers were at a loss on how to calm down my child etc.
When my child was six, i began a full time undergraduate course. I went to the uni financial advice service and they were fab. I got a lone parent grant, childcare grant, and a discretionary fund to make up the extra costs of having to enrol my child in a specialist breakfast club.after school club. They also told me about DLA and i was awarded HRC and LRM. My child's life totally turned around.
Five years later, i'm now in a full-time professional role working Mon-Fri 8am-6pm. Still single though and still having to claim some tax credits. My child's DLA goes towards specialist childcare around school and in holidays (although i i keep my annual leave for holidays but it doesn't cover all of them).
I don't mean for this post to sound like 'if i can do it, anybody can'. I just hope it offers some hope that it is possible to work/study when you have a disabled child and are a lone parent.
You just need to know where and who to ask for help/guidance.