I split up with exH 2 years ago, we have 2DC aged 4&8 and when they're at ex's they still see their cousins and aunty, my exSIL. ExSIL has only contacted me once since the split - to remind me to get her son (DN) a present (I refused said it was Ex's job now) - never checked to see I was ok after her brother had an affair. Anyway, her DS is 7 and over lockdown I allowed DD (8) to use my phone to face call him and play Minecraft with him at the same time on my iPad.
DN has his own iPad but he uses his parent's Facebook messenger accounts to face call DD.
Now we're back to normality, and school, I let DD have 3 hours in total on a weekend, split however she likes from Friday evening to Sunday. She used most of it on Friday after school, so that's her time used up. But DN has called (which came through to both my phone and iPad) 23 times. I didn't answer either as they've been in another room most of the day. I also had nuermous messenger messages like "DD call me now" and "Why aren't you calling you're upsetting me". I did reply sorry DD won't be having screen time today, but he still kept calling.
Anyway, I texted exSIL on the number I still have for her and said "Hi it's Glummy, can you stop DN from calling my messenger please, DD isn't allowed her iPad today and he's called 23 times today". She replied saying "OK but there's no need to be a dick about it he just misses DD that's all"
I don't think what I said was dickish at all. I'm tempted to reply and ask what she means. I haven't yet, but it's really bothered me. There's no backstory we got on fine when I was married to her brother but she firmly nailed her colours to the mast when we split (except when she wanted her son to get a birthday present, apparently that was still my job and if left to ex he wouldn't have got one 
)