TL;DR at bottom.
So, a good few years ago my younger brother had a daughter (I'll name her 'L'). My brother lives 4 doors down from my mother and took full advantage of the fact he basically had a baby sitter where he could take L and go run errands/work etc. My mother got a bit sick of this as she felt like she was taken advantage of.
So opted to start charging my bro a £5er (about $8/$9) each time he took L around and left her there.

As my Bro is a bit of a cheapskate, he stopped taking L around as often, opting to take his daughter with him on errands.

Fast forward 4 years, I have my first son in Jan 2018. For the first 5 months my amazing wife bends over backwards for him. During this time my mother in law visited constantly, helped my wife whilst I was at work. Including taking my son for a day or so, so that my wife could catch up on sleep and other odd jobs. My mother visited *twice*, which only happened due to me calling her and prompting her to come visit. (we live 3 miles away, about 10 minutes by car maximum). 

 When my wife needs to return to work (I'm a full time chef, so work 5 x 12 days a week usually). We arrange childcare with our parents to save on childcare costs, as we're saving for our own house we cant afford to put my son in a nursery. 

My mother in law is to have my son on Monday and Thursdays. I look after him Tuesdays and Wednesdays (my set days off from work) and my mother takes him the Friday. My wife has him on the weekend. 
(This is only whilst we're at work, my wife collects him when she finishes work. usually from 9am till 5pm, with the exception of Fridays which is 9am till 2pm)
After a month I get a text requesting from my mother asking me to pay her. 
After a bit of a debate, I cave and just give her some money. 

Fast forward a month or so, it's the six weeks school holidays. So my wife (a secondary school teacher) is off work for 6 weeks. During this time, the mother in law does her usual helping out. Takes my son for a day, comes around and supports my wife etc. 
My mother doesn't see hkm at all. 

The only time my mother sees my son, her only grandson. Is when I pay her to do it.

I really don't want to pay her. To the point that I actually feel like cutting my mother out of his life. 

AITA? 


FYI, we pay for food/milk/activities that either mother/mother in law does. So this charge I have to pay my mother isn't to cover expenses such as that. 

Mother in law works as a locum Dr on tues/weds other than that she's retired. My mother hasn't worked for approx 18 years.

TL;DR
My mother in law sees her grandson all the time. My mother only sees her grandson, if I pay her to  do so, but I don't want to pay her to be part of his life. 

Apologies for format, I'm on mobile. 
