Creative excuse

3 yr Nathan and 9 month Winston as much as they love each other, the fight for toy already arrived our home. Many Winston's toys were hands down from Nathan. Even though many of them he didn't play for a long time, once Winston played, he will recognize them and got nervous and told us "it's mine, it's mine". And yet sometimes Nathan is very willing to share.... Tonight,before the kids fall asleep, we were playing on bed. Nathan brought over a little airplane and wants to share. I told him" it's too sharp, not safe for DeDe (little brother in Chinese), it's Nathan toy, not Winston's toy! Nathan understood and put away. Later...I gave Winston a little "flatted " balloon that he recently so in love with to play. However, Nathan right away rushed over and wanted to pull away the balloon. He looks at me and said "mommy, balloon too sharp, not for dede...'. Mine........Nathan is getting very creative to come up excuse why certain toys not for share..and copy our words for different purpose so soon. It's wrong and yet just can't help to feel funny of it.