Well, obviously my DS and I have a unique relationship, because if I for one moment thought that his actions were affecting DGS badly, I'd have some very strong words with him, and he'd expect nothing less!
If it was my DDiL being aggressive, then I'd point it out to DS and expect him to do something about it.
Advising anyone to contact social services in a case such as this is wrong in the extreme, and a dreadful knee jerk reaction. Absolutely ridiculous advice to give!
Maybe my family are odd, but we're all firmly of the mind that 'it takes a village to raise a child'.
Not in the literal sense obviously, but in the not so distant past if a young mum had a baby who wouldn't sleep, or a newly-married couple had the row of a century, or a child needed advice with a school project, there would very likely have been a grandparent, an uncle, an aunt or a cousin just down the road who would be able to give much-needed reassurance, advice and support. But today many are parenting without family or even friends nearby, or if they are, they won't 'interfere' and we are all the poorer for it.
As for young parents threatening to stop GPs seeing the children, they should take a step back, inhale deeply, and damn well grow up!