To ask for half of my lost wages

[Cheery1004]

My son is running a fever atm. He's teething but at nursery if he has a fever after they give him 1 lot of Calpol they will ask for me or his DF to pick him up which i understand.
My and his DF aren't together. 9 times out of 10 it will be me who collects DS. Now I've reached my sick days in the year (4) I no longer get paid if I have time off. My ex at his old job was the manager and most of the time made excuses to why he couldn't collect him. Now he's in a new job which he's been in for a month so I get asking to go home for DS will be more difficult atm. But AIBU to ask him for half the day of my lost wages. I wouldn't be in this position if he shared picking DS up equally with me.

Oh and I forgot to say obviously I work part time and my ex works full time so the financial impact is much bigger on me not being paid for half or 1 day!

You can ask but legally he does not have to unless these sick days are on his contact days. Are they?
My partner and his ex have 50:50 custody. Child sick on his contact day it's his responsibility, child sick on her day then it's hers. Obviously there is a small amount of flexabity but that is generally how it works.

He is suppose to have him tomorrow night so yes I guess it is his day.

How to do you work that? Today wouldn't be his day if contact isn't happening untill tomorrow, tomorrow would be his day

That's what I'm saying tomorrow my DS might have to be off nursery. And his DF is having him in the evening