DD1 is 27 months old and dd2 is 7.5months old. Ever since DD2 was born, DD1 has given her a little kick or hit...we always say to her be nice or gentle, shes only little. I make sure I spend plenty of time with DD1 so she doesnt feel jealous.

So more recently, like the past 2 weeks, DD1 has been doing terrible things, like laying on her, kicking her in the head, more recently has been running up and jumping on her head with her knees, or just jumping up and down on her with her knees. Its getting to the point where it is happening all the time during the day. We have tried talking to her, naughty corner, time in room, smaking (no judgements please) and taking her dollies away. Nothing seems to work. She seems to understand that she is hurting her sister, but continues to do so.

The other thing I have noticed with her is she is also starting to test her strength out on other kids. We were at the shopping centre change rooms and she started to push another girl. She also did this to a friends younger child.

I am concerned that she will really hurt her sister. I wont leave them at all alone, but sometimes its hard when I turn away...

Is this considered 'normal' behaviour at 2 and is it just plain old jealousy? I dont know what to do with her anymore, I feel so sad for DD2. Do they grow out of it? Gosh we are even thinking of ttc #3 but it scares me that shes going to break one of them....or me!