First you try to think that what is the thing or action due to which they mind it.
If you get one try to remove it.
The child hood period is very small. It will just go like that in later life all of you miss it. Your sisters are younger to you.
It is good that you are kind to them.
Try to play with them.
Tell them nice stories. Give them small gifts.
Because if you love some one. It must be shown by your action.