Our JR is 5 now, we've got 2 DC's aged 3 and 18 months.
The dog is a joy and always has been, I'd agree with LaaDeDa on lots of points -
not motivated by food,
always quivering and sniffing around,
ours isn;t yappy and has barked about 6 times in her life!
Will stand up for herself with MUCH bigger dogs, but never starts a fight.
We've got a big garden and she tires herself out running up and down chasing the squirrels, she loves a walk and we take her everyday, but she's a real lazy soul around the house and is always curled up on a cushion in the corner of the sofa!
She'll chase any small animal and we can't let her off the lead because of it.
She's never snapped at the kids, although they are very good with her. She is getting a bit fat due to the amount of food the kids 'accidentally' feed her!
Would agree with SlartyBartFast that they need a firm hand - she likes to know her place and can be 'rude', jumping up, snaffling food off plates, trying to push people off the sofa etc. if we're not very firm with her!
She's got a crate that the dc are not allowed to touch, so she sometimes escapes to that if it all gets a bit much.
I LOVE JR's and would def have another.