Usually I am very careful not to comment on other people's parenting styles, believing wholeheartedly that what's "right" is different for different children and for different families and also, that we will never really know if we got it right anyway. I try to be especially careful where children older than mine are concerned, as if you haven't been there how can you possibly know what it's like?
My friend's DS2 has always been hard work, at 2 he was the most boisterous child at toddler group, at 4 he kicked my Dh hard and deliberately whilst playing football and at 5 he painted eyes on their car using gloss paint!!!
Now at 9 he is almost as big as her and starting to really rule the household. I'd go as far as to say she's scared of him, certainly of how he can react, so she does her best not to create situations to set him off. This means he is rarely told no and has few boundaries. Her DH has lots of rules, but does not enforce them. He will threaten grounding for a month etc, but it never happens.
She knows she needs to be firmer and tries, e.g. she'll say no you can't go out on your bike, because you didn't come home at the agreed time yesterday, but after 30 mins of shouting, she'll give in. When he's with his parents his behaviour really is appalling, but he's apparently well behaved at school and when I've had him, whilst a bit cheeky, he's generally been OK.
She been crying to me about him recently, but as soon as I try to give her any advice, I can hear myself, that it sounds like nagging. What can I do to help?
I struggle with this one as I don't read the cues, "I don't know what to do" doesn't mean tell me what to do, but usually a plea for sympathetic ear/ a sounding board - even though the solution might seem obvious to an outsider.
She may not want help, but it sounds as though she needs some. Could you invent a friend who got help somewhere? The Webster-Stratton type parenting courses are highly regarded (ask at SureStart or somewhere like that)