We've already received some email comments about this, so because it is currently his public profile picture, we're passing this along.
Jacob Mueller is of course the best friend of Jeremy Roloff, often seen in the Little People, Big World episodes with Jeremy. Most people know that Jeremy and Mueller are quite intertwined in just about everything they do. Ever since people noticed Jeremy's dramatically different physical appearance over the past year or so, people have been specualting and questioning how Jeremy and Mueller have achieved their new muscle-bound looks.
We're not making any claims of course, people form their own opinions as they should, however the above picture did startle some people, so we're passing it along because people are talking about it.