Tantrum?

Yesterday we think Jake threw his first fall on the ground tantrum. Rett gave him water instead of milk and Jake calmly walked into his playroom, set his cup down and laid on the floor on his stomach. All in complete silence and very carefully. He laid there for about 10 seconds, got up and drank his water. Rett said, 'I think he is throwing a tantrum.' He must have seen a kid do this but forgot to listen to them screaming...and forgot to see them throwing something...and forgot to see them cry...