Picnics - don't mention them! If I do make it to the mumsnet picnic in Bath, I will only be able to talk to people if I leave my toddler behind. He's a bolter, just like Dixie's and Liamsmum's toddlers. And my older son was both a bolter AND a dawdler. Still is to a lesser extent and he's nearly 8 years old. At least he has more road sense now.
You'll be sorry to hear I was hopeless at changing his bad walking habits when he was a toddler. I used to end up giving him piggybacks everywhere, just to keep us safely moving in the right direction.
A suedomim says, I think at 21 months, a toddler is on the young side for reason and reward, but the suggestions in mollipops message sound great for an older toddler. My other son is over two and a half, so I'll use them for future reference.
My toddler does walk better than my older son at this age. His childminder got him used to reins, (my oldest son was never on reins much) so I am now continuing with this. I say 'pushchair or reins', and explain we're near a busy road, so he can't walk by himself.
It's no good making him hold hands, because he is adept at twisting his hand out of mine. Holding him by the wrist works for short distances, but has to be done so firmly that it makes both of us stressed and angry - and I am bending down uncomfortably, making my back ache.
As we go, I make a point of talking to him about the way roads work. I very much like mollipops idea of giving positive instruction here, like 'keep on the pavement' rather than 'stay off the road'. I have to say, though, that dramatic danger warnings pepper my positive comments, too. I am hoping to instill a sense of danger in the bolter.
As your toddler is just 21 months, Liamsmum, you've a way to go before you see some road sense emerging. But, IME, the first signs of this happen sooner than expected. My toddler will now keep to the pavement much, much, more than last summer - but still not enough for me to let him run out of grabbing distance.
As for bolting at picnics - my only suggestion is to bring along some toys to keep the toddler close at hand - even consider a small inflatable paddling pool filled with water from a nearby tap, with some plastic cups to fill - he could help wash up the picnic stuff in it. I spent a fortune buying my toddler cheap plastic toys last summer to keep him occupied when we had to stay together outdoors. I predict I'll be doing the same this year.
Ha, but he's now just old enough for one strategy that worked and still works a dream on my oldest son. When he runs off in the opposite direction, or won't follow, I call him firmly, then, after several warnings I say 'bye bye then' and begin to walk away without looking back. Count to five and the toddler will run after me. My toddler is worried enough to follow me, but not mega upset about being abandonded by mummy. Some toddlers might be, of course. I pass on this tip because it's worked well with my two. And obviously I only do this if there are no roads, rivers etc. around.
Anyway, liamsmum and dixie, you have my sympathy. I'm looking forward to finding some failsafe tips on this problem, too.