Hopefully this will make sense as I'm still raging 
ExP and us have a 2 year old DS. We separated before he was born, in which time ExP quickly moved in with another woman and had another baby that was born before DS turned one.
DS is not a bad child. He is still 2 so of course prone to the odd tantrum or silliness, but in general he is an absolute joy. He's going through a bit of a shy phase at the moment, where he will take about half an hour to feel comfortable around someone he doesn't see all the time, and then he's fine.
When ExP picked him up today and told me he hadn't been 'good' last weekend as he was being shy and silly around some of ExP's family. ExP has been quite flaky with contact so DS isn't very familiar with them. I told ExP it wasn't an issue, DS is just being 2 he's not being 'naughty' and he will get over it in time. ExP shook is head and told me I let him get away with too much and I need to 'do something about it'.
AIBU to think he's an idiot who has no idea about kids and should keep his parenting advice to himself?
I told him to just go and we will talk another time because I didn't want to get angry infront of DS, and I know my anger is also fuelled by the fact that he has minimum input when it comes to DS so I feel it's a cheek him telling me how to parents. I want to rant and rave and tell him rather than blaming DS maybe his family should look at why DS isn't comfortable around them but I know that's probably quite bitter of me.
Am I 'letting him get away with too much' or is this just a normal phase? I really don't see what he wants me to do about it, I can't sit my 2 year old and lecture him. And I don't want to punish him for feeling shy?!