Pirate couple Brandiday became wealthy and decided to go into legitimate trade. This was mostly because they discovered they were pregnant. They traveled to the city at the Center of the World to start a trading business. They struggled with being landlocked and spent many a day in the wild nature of the XX city park. They soon discovered this little haven of wild in the city was run by followers of Gozreh. As worshipers of the 'Wind and the Waves' themselves they developed a quick attachment to the clergy. So much so that they decided to name their girl after the chief priestess: Evigail.
Their son was born shortly after. It was disappointing to the couple planning on a girl. As was much of his life to them, keeping your room clean, study hard, join the swim team, learn to dual, or navigate or sail or any other things they deemed normal. Evigail did as they asked, but only in so much as they asked. Though they wanted him to be a priest of Gozreh to help the trading on the seas, he instead learned more about plants and wind. In every aspect he has taken the path of least resistance that still met his parents wishes.
His tendency to go with the flow, plus his aptitude for plants, earned him the nickname Seaweed. Though his parents would have preferred something more 'legendary' as pirates go this is as good a moniker as any, and since he didn't fight it, the name stuck.
So he joined the pathfinders, a bustling presence in the city with much need of clerks and other beureucrats. Thus he met his parents wishes of becoming 'legitimate' without being involved in trade, and has to occasionally board a ship and leave the city.