My 4yr old daughters behaviour has taken a turn for the worse

[beanie430]

I am worried about my 4 year old daughter,
she was until about 8 weeks ago the most quiet, polite, helpful & caring child. (she is number 3 of 6) we often said that we wished that all our children had her personality. Now she is agressive, throws tantrums over nothing while screaming blue murder, straight after that it is not uncommon to see her litterally "pass out" asleep. She has been fully toilet trained both day & night for over a year, yet now she poos & wees her knickers, night nappy etc all the time. She will not tell you she has done it, only smiles when you ask her (smells) she also puts on pants to cover it.
she has become really demanding, has insomnia also. We live in a high lead environment (google mount isa, australia) and i am wondering if that has a role in this? As for the stress level we have just had a baby 6 weeks ago, but they are all really close in age, so nothing there has really changed. She has started kindy 9 weeks ago, on her 1st day she wet-but this was put down to the fact that she was too shy to go to the toilet. we havent had a problem there since that 1 time. She is a very petite child she had IUGR when she was a fetus & has stayed small. She wieghs 11kg now at 4yrs old-again not good for a lead environment. Her last community lead check was 6mths ago where it was normal.

i have done childcare for 10 years now and my evaluation is that her personality has done a complete 360 degrees.

please help!

[beanie430]

Yeh we tried the extra attention giving, but it just makes her worse :(
This started pre-baby as well. We have 3 year old twins that are more demanding on my time then any of the kids-baby included. We have discovered also that she is pooing in her sleep as well, so i have just about ruled out a jealousy cause. Going to get her lead tested tomorrow to rule that out, because all the symptoms fit with long-term lead poisioning too. Very confusing :/
thanks anyway :)

[margypops]

It is possible that she has jealousy issues over the baby, the older children often go through this, she sees the baby wetting and pooping in her's  /his diaper and is emulating it, as she sees that baby gets attention after he has done it. I suggest some extra one to one attention from you and her Dad, she is feeling usurped, left out. Let dad watch baby and you do some reading, drawing , going to the the park with her . then ask Dad to give her the same , make more of her, she deserves it. Focus on her positive side and praise her when you see he doing something right, Let her help bathe the baby, play with toys with him .Good luck this is very common .