Jo's relationship with Professor Bhaer surprised readers who expected her to end up with the charming and wealthy Laurie.
Bhaer was not a conventional romantic hero in any way — he was poor, middle-aged, foreign, and somewhat unfashionable.
But he offered Jo something that Laurie, for all his charm and his obvious devotion, could not offer at all.
He offered her an intellectual companion who took her writing and her thinking seriously as a genuine partner would.
Their conversations were the kind that changed how each of them thought about things that mattered to both of them.
Jo did not fall in love with Bhaer despite his lack of conventional attractions but because of his unconventional ones.
She needed a love that made her grow, and growth was exactly and specifically what Bhaer's company produced in her.
True love means growing together.

The critical controversy over Jo's marriage to Professor Bhaer rather than Laurie has never entirely been resolved.
Many readers feel that Alcott made the wrong choice — that Jo and Laurie belong together and Bhaer is a consolation prize.
But this reading misunderstands what Alcott was attempting to show about the relationship between love and personal growth.
Laurie loves Jo completely, but his love is essentially static — he wants her as she is and would prefer she not change too much.
Bhaer's love is dynamic — it assumes that both people will continue developing and expects the relationship to develop with them.
For Jo, whose essential project is the continual development of her mind and her craft, only the second kind of love will work.
A love that preserves her as she is would prevent her from becoming who she is capable of being — which is not love at all.
Alcott's choice of Bhaer is not a disappointment but a careful argument about what genuine love looks like for a person like Jo.
True love means growing together.