Sounds like you and McGilla need a hobby that keeps you busier than boating. If memory serves......he's expecting also.
Give up the boat, 'cause the next 5 years of your life are going to be centered around the baby. Keeping the boat will just make you depressed by not being able to use it. If she gets pregnant again, return to go, pass up th $200 you thought you were getting, and start from scratch again.
It's ok, though.......the babies are worth it.
I've heard that babies like boating, so ad a seat and give it a try, maybe you'll get lucky.