To call off work

[mammabing]

DS is usually looked after by my mum whilst I’m at work part time. I’ve recently had to change my contract to cut my hours down as she can’t have him for as many days as planned initially. She rang this morning to say she is unwell and can’t have him this week. DHs parents are unable to help out and we have no one else to ask.
AIBU to say I’m unable to go in this week for childcare reasons? I’m concerned they’ll say yes to being off tomorrow but I should sort something for Tuesday. Trouble is there is no one else I can ask! We’ve got him on the waitlist for a nursery and he’s due to start in a few weeks time.
DH works at the same day place as me so either way they’re down a staff member.

We’ve got him on the waitlist for a nursery and he’s due to start in a few weeks time.
Good. This is useful as if they start to say you are unreliable you have already got a solution.

Why don't you ask to go off tomorrow and your dh on Tuesday? That's what usually happens with me and my husband. So we both take the hit.

Contacted work and they were fine with me being off as we had no other option. We rang so many people but no one could help and I don’t feel comfortable leaving him with someone I don’t know.
I’m intrigued about the poll results - 83% of people thought IWBU to call off. Anyone who agrees with that I would genuinely love to know what they would have done in my situation? I couldn’t see a way round it but if there is I’m open to hearing it.
Unfortunately my mums illness is a long term thing which is why we’ve signed DS up for nursery - he wasn’t due to start until September but my mums health takes priority.
Also just in case anyone is of the opinion that I just leave him with my mum, she offered. She’s obsessed with him and we pay her, although usually she transfers the money we give her straight into DS’s bank account!