The three teenagers regularly shared silly videos, trying to one-up each other and trusting the group text messages would remain private.
But one especially sensitive text did not stay among them - landing the teen who first sent it at the centre of a novel court case over a sexually explicit video she made of herself and shared.
Maryland's highest court will soon decide whether state laws intended to stop child pornography apply when the child is both the subject and the sender of the graphic material.
The case stands out for its unusual circumstances even in a "sexting" era when judges, lawmakers and prosecutors throughout the country struggle with how to reconcile laws crafted before the era of cellphone videos with evolving technology and teen behaviour.
In the Maryland case, the then-16-year-old sent her one-minute video to the three-person group text chain.
A few months later, the group "fell off as friends," according to court records, and the students who received the text shared a copy with their school resource officer from the Charles County Sheriff's Office. By then, too, one of the teens had shared the video with other students, court files show.
The only teen charged was the teen who made the video of herself, according to the county prosecutor, setting off the chain of court action now awaiting a ruling from the Maryland Court of Appeals.
Prosecutors in some states have charged teens with possession or distribution of child pornography. In a Fairfax County case, three teenage boys were found guilty in 2013 of unlawfully producing videos of teen girls. They initially faced more serious child pornography charges.
State legislators have also rewritten laws to impose less severe punishments that account for the immaturity of teens. The Virginia Senate last year passed a bill that would have kept teens from being labelled as sex offenders for willingly sharing nude images with each other. The bill that would have made sexting among minors a misdemeanour stalled in a House committee.
The case in Maryland raises questions about how to treat teenagers who voluntarily self-produce and share their own sexually explicit images.
"We can't have a cookie-cutter response," said Catholic University law professor Mary Leary, who has written extensively on the legal response to self-produced child pornography.
Prosecutors, she said, should have discretion to consider a list of factors before deciding whether to bring charges, such as the role the teen played in production, how widely the images were distributed, and whether the teen can be helped with or without involvement by law enforcement.
"We should resist having a firm rule," Leary said, and instead account for different circumstances, for instance, between a teen willingly sending a picture to a romantic partner and a spurned boyfriend or girlfriend widely circulating such images.
In the Maryland case, the one-minute video depicted the girl performing a sex act on an unidentified male. The girl, who is referred to by her initials in court records, texted the digital file to the cellphones of another 16-year-old girl and a 17-year-old boy in October 2016.
The teen who originally made the video was charged in juvenile court, where her two friends and school resource officer testified, court records show.
At her initial hearing, the prosecutor said the state was not "trying to prove a point in going forward with this case," but that "the state believes that the respondent is in need of some guidance, rehabilitation for something deeper" and "is just trying to help her."
Because her case on the distribution of child pornography was in juvenile court, the teen never faced a mandatory sentence the possibility of having to register as a sex offender. She was put on probation and referred for a mental health evaluation.
She and her family appealed the court decision and judges at the intermediate appeals court largely upheld the the initial ruling.
The Court of Special Appeals - which is one step below the top Maryland Court of Appeals - sided with the state in ruling that lawmakers had not included exceptions for consensual sex or for self-produced child pornography.
"The state has an indisputable interest in protecting minors from exploitation 'as subjects in pornographic material' . . . whether at the hands of others or by their own conduct," wrote Chief Judge Matthew Fader, who was joined in the decision by judges Kevin Arthur and Raymond Thieme Jr.
"Unless and until the General Assembly exempts from the reach of the statute minors who distribute materials depicting their own consensual sexual conduct, that conduct is prohibited,' the judges wrote.
In the same ruling, however, the court rejected the finding that the teen was responsible for "displaying obscene material" to a minor because it said the law does not specifically apply to the technology she used - a digital video file - to share the material.
On appeal at the state's top court in February, the teen's lawyer from Maryland's Office of the Public Defender, Claudia Cortese, said that the teen's conduct was voluntary and legal: The law cannot be applied to individuals who, like her, were engaged in consensual sexual activity.
"The statute is intended as a vehicle to protect, not prosecute, minors victimized and exploited in the production of sexually explicit videos," Cortese wrote.
The age of the male in the video is not part of the case record, and both sides said in court filings that the footage suggests he was at least 16.
Letting the decision stand against the girl stand would amount to convicting her as her own pornographer for forwarding a cellphone video of herself to two people she considered her best friends, the girl's lawyers wrote.
Maryland Assistant Attorney General Sarah Pritzlaff countered in filings that the court cannot ignore the possible harm to the teen from her shared video and that overturning the conviction would disregard the legislature's interest in protecting minors and stopping child pornography.
On the separate question of how to interpret the law, Pritzlaff told the court that the word "film" in the statute should be read broadly to cover digital video files sent electronically just as the definition of photograph in the law no longer applies just to hard-copy pictures.
The teen in the video was so upset about the file being circulated more widely that she did not attend school for a month, her mother said, according to court records.
"When you create a digital image, a depiction like this, it is a permanent record," Pritzlaff told the court. "These images are getting out. It's not at all surprising in this case that there was a falling out among friends and that this video got out and was all over school."