Funny you should ask that; I've been searching for John BOEHLER's siblings for a while, with no luck. Recently, I did come up with one:
Henry BOEHLER, b. 1841 in Rhinehessen, Ger.; m. Aug. 1886 in Milwaukee, WI. He was a taylor who fought in the Civil War.
I know that doesn't help much, but right now it's the only other name I have. (At least, for me, it indicates a link to the Milwaukee BOEHLERS, of which there were many.)
Conrad's BAILER surname -- if it wasn't just a mistake by a Census taker -- is an interesting twist. Although my GGGrandfather John was adament about spelling his name BOEHLER, his son changed the family name to BAILER at the turn of last century. I have long wondered why he chose that particular spelling.
I wish I could be of more help. Mecklenburg is a considerable way from Rhinehessen -- and John is definitely from Wonsheim, Rhinehessen, Germany -- but there's always a possibility they could be related.
Unfortunately, if there is a link, I haven't found it. Yet.
Let's keep in touch.