Sully argues with Mike that they should move if the railroad comes. Meanwhile, Matthew feels left-out of Sully's new homestead plans.

Loren plans a trip to Bolivia to prove he is not getting old; Brian seeks to prove his courage by camping out alone. The two become inadvertent allies as they battle the advances of a hungry bear. Also, Jake and Hank's practical jokes get out of hand, culminating in injuries to them both, until they agree to make up

Mike receives a telegram from Miss Olive - she's ill - but when she, family and friends arrive in Mexico, Miss Olive's already passed away and left 200 cattle to Matthew. Now they must get the herd back home. Colleen gets a crush on a handsome ne'er do well cowhand named Jesse, only to be robbed and deserted by him.

Matthew and Sully quarrel over the route of the cattle drive.

Mike tangles with the usually benevolent Reverend when she donates books to the town and he tries to ban them, ultimately burning some of them until Mike brings him to his senses. Also, Brian, influenced by Twain's ""The Celebrated Jumping Frog of Calveras County,"" stages a frog-jumping contest with disappointing results.

Mike, Sully, and Cloud Dancing head to Washington, D.C., to lobby on behalf of the Indians.

Sully is imprisoned when he accompanies Dr. Mike and Cloud Dancing to Washington to lobby on behalf of the Cheyenne.

Mike and Sully battle money issues when Sully wants to be the primary provider and Mike wants to combine their incomes - in the end, it's Sully who comes around. Also, Myra becomes a sleepwalker, driving Horace crazy, but happily, the sleepwalking turns out merely to be a symptom of Myra's pregnancy.

Mike and Sully run into now-married Kid Cole and Sister Ruth and invite them home for Thanksgiving, but the coach is hijacked, forcing them to journey home, on foot, through Indian country. Also, the Cooper kids scramble to put Thanksgiving supper together. Kid Cole: Johnny Cash. Sister Ruth: June Carter Cash.

Mike discovers a lump in Dorothy's breast and performs a mastectomy on her. Meanwhile, Colleen must deal with the unwanted attention of a new boy at school who fixates on her impressive bust. Finally, Jake, dressed in drag for Ladies Night at Hank's saloon, gets kidnapped and held hostage by an amorous outlaw, but escapes.

Dorothy insists the decision to have surgery is hers, not Mike's; Colleen finds the harassment unbearable.

Mike intervenes in their behalf when a Jewish peddler family arrives in town and is met with prejudice and harassment from townsfolk. Also, Matthew masquerades as Santa Claus for Brian. Guest star: Trisha Yearwood

Sully takes a job as an Indian Agent, only to discover corruption's rife within the system. Meanwhile, liquor arrives on the reservation, and Snow Bird miscarries due to malnutrition.

Mike remains the sole voice of reason when townsfolk read a newspaper article predicting that a comet will end the world. Also, Mike addresses the Cooper kids' fears about ""the end."" Hank and Loren cash in on hysteria.

Mike learns some patients are beyond help when she climbs Pike's Peak to follow a woman who's chosen to die in its rarified air rather than continue to battle leukemia; Grace deals with her jealousy of Myra's pregnancy. Colleen delivers Myra's baby in Mike's absence, ushering in a new life for the one lost. Sam Lindsay: Eve Brenner

Mike loses custody of Brian and Colleen when their father, Ethan Cooper, arrives with new bride Lillian and reclaims them in a messy courtroom battle. Also, Myra and Horace are almost driven out of their minds by new baby Samantha's incessant crying.

Brian and Colleen run away from Ethan and Lillian, and Colleen contracts potentially lethal pneumonia, which, upon the kids apprehension, Mike treats. Also, surprisingly, Hank's the only person who can quiet Samantha, Myra and Horace's eternally crying baby.

Brian's homework assignment, an essay entitled, ""What Is Love?"" to be written in honor of Valentine's day, coincides with Dorothy and the town's production of ""Romeo and Juliet."" Also, Becky and Colleen compete to play Juliet, Dorothy and Jake split up, and Sully gives Mike an engagement ring.

Mike volunteers Robert E's services to fix a steam engine for the railroad, but whether Robert E can do it remains in question until the job is completed. Also, Mike solves a medical puzzle when two Chinese railroad workers, the Chang brothers, fall strangely ill. Jackson Tait: Allan Royal. Peter Chow: Eric Michael Zee.

When teen-outlaw Belle Starr robs the saloon, Mike takes her in, intending to reform her; Colleen overcomes her fear of riding. Belle Starr: Melissa Clayton.

A paleontologist arrives in town, igniting ""bone fever"" among the townsfolk when he announces that dinosaur bones are worth money. Meanwhile, Matthew and Colleen try to prevent Brian from discovering that the ""dinosaur"" bone given him by his pa is fake.

With no child-protection laws, and influenced by Charles Darwin's theory of evolution, Mike has a girl removed from her ""guardian"" by taking the man to court and trying him for animal abuse. Mary Ann: Doren Fein.

Mike and Sully arrive too late to avert Custer's slaughter of the Indians at the Washita River; Brian befriends an Indian boy destined to die at Washita; Robert E & Grace attempt to adopt an Indian baby whose mother was killed at Washita. No Harm Comes To Him: Sean Price-McConnell.

Sully and the kids must help Mike deal with the emotional aftermath of the Washita massacre; Robert E and Grace must return to Cloud Dancing the Indian baby Mike and Sully brought back from Washita

After discovering a badly injured Loren, Sully must battle his own demons in order to save him.

Mike and Sully go to the Reverend for a dose of preventative pre-marital counseling, and recall the path of their romance.

Mike's mother arrives with elaborate wedding plans; Custer puts a bounty on best man Cloud Dancing.

While Sully is off thinking and doesn't return for several days, Mike gets worried. Although Mike continues to believe in their love. When Sully finally returns, Mike realizes she just wants Sully as her husband. Mike and Sully marry on May 20, 1870. Brian, feeling left out, has a surprise for the newlyweds.