Daughter kicked in stomach by older sister

[Anon501178]

My oldest daughter is 8.She has ASD and can struggle alot with emotional regulation.
My 3.5yo just slapped her and my 8 year old got very angry and instantly lashed out back, by kicking her multiple times in the stomach area (think punching like in a boxing movement, but with her feet instead of fists)
Would you be getting youngest DD checked out incase of internal injury?
She seems fine at the moment- cried lots when it happened and coughed slightly but recovered minutes after.Oldest DD had sternly been told never to hurt her in that way again despite it being a knee jerk reaction and her now being remorseful.They are now playing like nothing has happened but I'm concerned as youngest DD's toddler stomach is obviously still quite fragile at her age!

I think it would depend on the force used. Could you ring 111 for advice? Did you see how hard the kicks were?

Edited to add that your 3.5 year should be told that slapping is never acceptable either.

Have you punished them both?

Yes I told them both off at the time- i was in the process of telling youngest off when eldest lashed out.It was fairly forceful as she was angry but I've rung 111 and they said as no bleeding, swelling, bruising, vomiting and she seems fine in herself to monitor at home for now.