Please help, my 21 month old is a nightmare in playgroup

[Tsarina1]

Hi

I am crying as I'm writing this my beautiful gentle little 21 month DD has morphed into an aggressive monster & I don't know what I have done wrong or how I can help.
We go to playgroup & she has started grabbing really aggressively, pushing hitting & the worst is she does is use both hands to pinch faces so severely she leaves a mark. I am her shadow in playgroup, I nearly always catch her in the nick of time & I always apologise to parents which in fairness are so sympathetic & comment on how good I am at anticipating her moods.
I don't know whats causing this her baby sister arrived 5 months ago & she is very good at her, it's just other children she lashes out at:( So I don't know if it's her sisters arrival but it doesn't seem to be as she is so good with her.
She has amazing vocabulary & speaks in full sentances. Before playgroup she tells me the rules no pushing, no grabbing, no pinching, play nicely with the toys & other boys & girls. She is getting her molars does this change behavious?
Please give me some advice I can't afford to put her in nursery, we have no family near by to support & we are fairly new to the area so havn't made many friends yet, the other moms in the group are very nice despite me being mummy to "that child" & I can't get to know them as I'm too busy with DD.
I feel quite sad that I'm starting to nearly disconnect with her, I can't bond with her like this she used to be so happy & friendly, used to play really well with other toddlers would never grab always share.
Please reassure me she will turn out ok!!!

DS (2.8) has been like this since the arrival of his sibling. I've found that the most effective strategy has been instant consequences. He gets one warning for pushing, if he does it again we go home immediately. No warnings for hitting/biting/pinching (thankfully very rare), that's an immediate red card. At the time it feels as though you're punishing yourself as much as the DC because you're then stuck at home with somebody whinging about missing snack time, but I think it is getting the message across that he can't hurt other children and get away with it.
Also, be wary of assuming that because her language is good that her comprehension is at the same level. Toddlers just don't get empathy, and it's only recently that DS has been able to describe his own feelings, let alone understand that other people have feelings too. She might be able to tell you the rules, but she is almost certainly unable to understand why they exist. She just wants that toy!

Please don't be sad about this, it's a normal phase and as long as you are consistent and firm with enforcing the rules she will grow out of it. Also (and slightly contradicting my earlier point) please keep going to groups, the more she is exposed to other children the quicker she'll get through it.

Thanks so much for the reply, it's so disheartening isn't it. Had some childminder today offering me advice grrrrr, told me to stop following her & let her to it!!!! Hello she woukld gladly have poked some poor childs out:( Thats exactly it Fay I need the group as much as dd does to break up the day & get to know the other nice moms in the group.Fel so sorry for dd2 as I dont have a second with her as dd1 is so challenging:(
Interestingly we do jo jngles & monkey music & she loves both & it so well behaved, I wonder is it due to the structure?
As I mentioned shes getting her 2nd set of molars can this also cause more aggression?

Not sure about the molars specifically, but DS's behaviour is certainly worse when he's tired or under the weather. On those days I might go to a group for half an hour, 45mins then go home for a quiet afternoon, rather than forcing him to stay somewhere when he's not feeling up to it.
And yes, structure can be good, I prefer groups with a few activities laid out, rather than the ones where kids just run around in a church hall. I think that sometimes that sort of group can be a bit overwhelming, particularly for the littler ones.

I'd also say, be careful not to get into a habit of only giving attention for bad behaviour. It's very tempting when they are playing nicely to sit down and have a chat to the other mums, but it's good to reinforce good behaviour with praise and attention.
Please don't worry, the fact that she behaves well in some situations shows that she can follow rules, it's just a case of her learning to do that in different situations.