Toddler hitting older sister (causing pain)

[Beppie]

DD#2 is 21 months old. She's always been a pleasant, cuddly child...no other behavior issues, in other words. But she hits her older sister (who is 4 years old) out of the blue. Last night she hit older dd with a toy, causing the older child's lip to bleed all over (a bit scary for us!).

We responded by giving all our attention to the older child (soothing her, fussing over her, etc.).

Is there anything else we can do about this, to get dd#2 to stop hitting?

[ssh]

With toddlers I've always liked using a time-in for antisocial behavior. Sort of 'If you can't play nice you can't play' so you have to sit with mommy or ride in the backpack on mommy for awhile. If it's happening more than every once in awhile you need to shadow your DD #2 and try to prevent it. 4 years old is still really little. She's probably really upset getting hurt.

[JL83]

We had good luck with "You hit, you sit"...

The hitter has to sit down where they are while you tend to the hittee. Once that's done you go to the hitter and sit with them and talk for a minute. If it's happening alot, then I turned it into them having to stay with me for a bit. That could be sitting with me on the couch or having to come to the room I'm in and "help" with what I'm doing.