I have given Seth more nicknames than I have anything else. But I think Moose tops it. Only because for his age (4months) he is built like he's older (6months) as well as a linebacker. I only thought of it because he let out the roar that was so loud my mom heard it probably like he was right next to her. Usually he generally is loud, but this topped them all.
The sound reminded me of a scene from the Princess Diaries when the hair styles had finished this outrageous do on Mia and was like,
"You look faboulous like girl moose. Make all the boy moose go wAAAAOOOOHHHHNNNN!"
And Seth sounded just like it lol. So he is dubbed (sometimes) Moose.