At its heart, the murder trial of Casey Anthony, accused of murdering her little girl, is a story about a family facing that horrifying dilemma.
On top of that, the defense's case alleges sexual abuse and dark family secrets. So when the key witnesses also are the defendant's own mother, father and brother, it's sometimes difficult to tell where their loyalties lie.
"They are conflicted, surely, because they want justice for their little loved one, Caylee," said Beth Karas, a correspondent for "In Session" on Tru TV. "But they also don't want Casey, for example, to receive the ultimate penalty of death."
A victim's family normally thirsts for a conviction when their loved one's alleged killer is on trial, but the Anthonys often sure do appear conflicted.
"I don't want to be here," said Casey Anthony's brother, Lee Anthony. "I don't want my sister here. I don't want my parents here."
The jury gained some insight into the unusual alleged family dynamics late this week -- and witnessed possibly shifting recollections -- as Lee Anthony described the pain of being left out of the loop on his sister Casey Anthony's pregnancy.
"They didn't want to include me, and didn't find it important enough to tell me," he said, prompting tears not only from himself, but also from his sister.
The brother's dramatic appearance on the witness stand clearly baffled prosecutors, who questioned the sincerity of his emotion and his memory, which seemed to differ from his 2009 deposition.
Further complicating the case, both Lee Anthony and his father, George, have faced unproven claims by Casey Anthony's defense that they sexually abused her, alleged behavior that the defense reasons could be a root cause of their client's bizarre behaviors and lies surrounding Caylee's death.
"This is a family that operates with a lot of what we call dissociation," said Dr. Terry Real, who has studied relationships as founder of the Relational Life Institute. "That is exactly what the defense is saying that Casey is about."
The unsubstantiated accusations of abuse could be a risky move by the defense, Karas said.
"If that's true, he should be prosecuted," she said. "If it's not true, it's a horrible thing for him to have to go through, to have to face the world knowing that [defense lawyers are] leveling these allegations against him."
Cindy Anthony, Casey Anthony's mother, also has seemed tormented at times, describing watching home videos of the life she once had.
"I've watched it thousands of times since I didn't see Caylee since 2008," she testified.
She's been in court almost every day and has taken the stand five times.
There's been no shortage of tears. At one point, she turned to her daughter, Casey Anthony, mouthing "I love you," but Casey Anthony wouldn't make eye contact, turning away.
And this week, Cindy Anthony's story about what she did and when seems to be shifting.
"Do you remember in March 2008 doing computer searches for chloroform?" defense attorney Jose Baez asked her.
Cindy Anthony responded, "I started looking at chlorophyll ... and it prompted me to search for chloroform."
Later, when asked by a prosecutor, "Did you put the words into the google search engine "how to make chloroform???" Cindy Anthony replied, "I don't recall if I typed the words exactly like that."
Prosecutors maintain Caylee Anthony was chloroformed before she died. Those computer searches could prove it was something Casey Anthony planned.
But if Casey didn't search for chloroform online, it could be harder to prove premeditated murder -- an idea perhaps not lost on this mother.
Real believes that ultimately any mother would do whatever was possible to protect a daughter.
"I think virtually any mother would lie to save their daughter's life," he said. "The maternal instinct wins out over virtually everything else."
ABC News' Jessica Hopper and Michael S. James contributed to this report.