"My First Veins"

Last night Jax was in the shower and he said, 'Mom you missed my first veins.' I said, "What do you mean?" He said, "you know my first veins, in my arm (as he makes a muscle in his bicep) b/c I am working out!" I said, "Honey, you have always had veins"...he said, "No, mom these are my first veins!" How could you argue with that?! I just let it go and said, "okay honey!"
Then today we were watching Full House and he looks at my feet and says "Mom you are working out b/c you have veins in your feet!" The only thing I can think is that he's seen body builders with big muscles and veins popping out and now he thinks that means you have worked out! LOL! He's so silly!