in answer to the original post and subsequent follow up, no we don't use anything we've termed "time out". dd is 2 yrs 9 mo and would be completely traumatized by a "mainstream" time out where she had to be by herself. she rarely leaves my side as it is. that would be real punishment for her. she is pretty spirited, though. very opinionated and much much more vocal about things than any of her peers. can melt into wails at any moment, but doesn't usually kick or hit. it has happened occasionally, though. we usually act very shocked and tell her that's not nice (not so sure of myself on that wording).
we're expected her little sibling in about a month, so i may be posting here with questions like laurag's then, but for now, as far as what i would do in the situation laurag described, i would probably let her look at the flowers for a little bit and tell her when she was ready we needed to get in the car and go. she's usually pretty receptive to this. we negotiate a lot. i also point out things on the way to the car or as we're leaving the park. "look at that pretty tree over there", or, "hey, we get to go across the baseball field", or, "look at that ant", etc, etc. all these things would be in the direction i wanted her to go. doesn't always work, but sometimes it does.
usually if, like zeal's mom, i acknowledge her feelings of needing to explore a few more minutes, but remind her that we need to go, she'll go. if she pitches a fit, which has definitely been known to happen, i don't yell unless she is running into traffic -- very appropriate time to yell imho, but grab her hand and hold her/pick her up and acknowledge her feelings -- "are you feeling frustrated because you want to look at the flowers some more?" if i'm having a rough time, too, i'll tell her my feelings, "i'm feeling pretty frustrated, too. i'm hungry and need to go home and have lunch. i get cranky if i don't have enough to eat." (dd gets cranky really quickly on an empty stomach, so i'm trying to get her to recognize when she's hungry. she's usually a happy kid if she's well fed.) after she's comforted she'll usually calm down enough to get in the car seat.
last night, though, we went to our local elementary school to vote. there was hardly anyone there and it wasn't very exciting, but dd pitched a fit when we left. dh was with us and he was holding her (she wasn't trying to run away) and asking her what was wrong. we figured out through the wails that she wanted to stay. there was nothing else to do there, so staying wasn't much of an option, and the polls were closing. we showed her some picnic tables on the way out (still wailing, but not quite as loud) and tried to get her to talk (she's very articulate when she's not too worked up) about what she wanted. dh was suggesting going home and swinging in her swing which she loves. we did put her in the carseat wailing. finally she said she wanted to go to the mall. that worked out great for us 'cause i really needed to vacuum and dd hates the vacuum. i usually sweep, but we just had a door installed yesterday and sawdust and drywall dust was everywhere and it really needed vacuuming. i had been waiting til dh got home to do it so he could occupy her. so we dropped me off at home and they went to the mall for an hour and a half and had a great time. i think she just wanted to be out and about some more because we had been home all day with the door guys. we all worked out a compromise that worked well for us. obviously, not applicable to all situations, but if we can get her to talk to us then we can usually go from there. might have to say we can't go to the mall tonight, but we'll go tomorrow or something, but getting her to articulate or at least giving a guess as to what's wrong helps us a lot.
for the diaper change thing, unless it was poopy i'd probably leave it or let her be nekkid. dd is potty trained (mostly -- peed on the rug today

: ) and looooooves to be naked. she's napping right now naked and has since she was a wee one. i don't think kids usually pee while they're asleep. it's when they rouse up that they go. just my experience.
btw, i don't like the infant buckets too much although we did use one with dd some and we still have it so we may end up using it with the new baby. i'm planning on slinging a lot more than i did with dd, though. really hope this kid likes the sling.
if anyone is interested in the negatives to time outs you should check out the gentle discipline forum. i'm sure the mamas there could tell you more about it. i think the folks who don't like them, though, don't like the traditional ones where the child is banished. the ones that most of the mamas here are talking about are much more loving than that.
oh, someone asked about standing on the arms of chairs. what i did with dd (not a very adventurous climber anyway) was to show her when she tried it how the chair would tip over. i let her put her weight on the back of the chair and let it start to tip, but i held her so she wouldn't fall. then i explained how she might get hurt if she really tried that. she's older, though, so i don't know if that would work with an adventurous 20mo-something.
hth, and really if you're looking for more creative ideas than time out, check out gentle discipline,
http://mothering.com/discussions/for...?s=&forumid=36 . the mamas who hang out there have great advice.
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