Dealing with Consequences

My oldest daughter Kayla is 7 years old. She's normally a very helpful, funny, kind-hearted girl. But lately she has had a very selfish, greedy attitude. I didn't know what it stemmed from, or even how to get it to stop. I tried talking to her about it, giving her scripture about what happens when you're selfish, I tried scolding her, I tried all I could think of and it wasn't getting any better. If anything it was getting worse. Maybe her selfishness was a way to get attention.
So I've decided something; I'm not going to accommodate her selfishness anymore, she's just going to have to deal with it, even when it hurts me too. Yesterday at church a sweet lady in the church brought some hats she had knitted. Kayla immediately snatched up a red and blue one and said "This is mine!" I wasn't near her so I couldn't say anything about it, but because she grabbed that one, there wasn't one for Lela, our (almost 6) 5 year old. But Lela didn't cry or complain, she just had a sad face and the lady said she would make some more that would be her size. Today she brought two more hats; a green and yellow one and a light pink and red one. Kayla decided she wanted to pink and red one also, and told Anna (2) that she could have the green and yellow one even though Anna got a pink one yesterday. That made Lela upset and she started to cry.
This is where I had to be firm with Kayla so she could see how her selfishness yesterday effected her today. I told Kayla that Lela got to choose first since she didn't get one yesterday and since Kayla had already told Anna she could have the green and yellow one, and Lela wanted the pink and red one, that Kayla had to stick with the red and blue one she greedily grabbed yesterday. She was not happy about this, and was upset for quite a while. But I hope she sees on her own that selfishness seems to get you a gain when you're in that moment, but in the end, it limits your blessings. If she had shared yesterday, she could have gotten the pretty one today. I told her "Sometimes your choices keep making bad choices for you." I'm praying she'll see that selfishness does not equal gain.