I have first-hand experience! My immune system slowly killed my liver (primary sclerosing cholangitis), and I had a transplant. (btw, for $0, thank you to the Australian health system)

I received a cut-down liver from the donor; I got the bigger lobe, a child recipient got the other lobe.

Within a few months of transplant, the new liver had regrown, but (probably because of the transplant orientation) rather than growing across to the left, it grew down the side of my body.

It's all good and functions fine, it's just that now my right-side of my body isn't as 'saggy' as my left because of the area it grew in to.

It's an amazing organ, and it truly sucks when you don't have a well-functioning one.