The parents of a baby who suffered broken ribs before being smothered have been found guilty of causing or allowing his death.
Stafford Crown Court was told two-month-old Tyler Morgan also had what appeared to be a human bite mark on his arm following his death in April 2014.
A six-week trial heard Luke Morgan, 26, and 22-year-old Emma Cole were heard arguing and crying at their flat in the hours before Tyler was admitted to hospital.
Jurors heard claims there was a "significant" delay in contacting the emergency services after Tyler's collapse in the early hours.
Morgan and Cole, formerly of Sunnymead Road, Burntwood, were also found guilty of child cruelty but were cleared of charges of murder and manslaughter.
The couple held hands in the dock and appeared tearful following the jury's verdicts following more than 11 hours of deliberations.
Opening the Crown's case at the start of the trial, prosecutor Andrew Smith QC showed jurors a picture of an injury to Tyler's right forearm which pathologists said was a "probable" bite mark.
Mr Smith told a jury of seven men and five women: "At 2.42am on the 29th of April 2014, Emma Cole dialled 999 to send an ambulance to her home address.
"Tyler Morgan, the nine-week-old son of the defendants, had collapsed before the call was made.
"The prosecution's case is that Tyler's collapse was caused by his being intentionally smothered or his chest being compressed.
"That intentional smothering and/or chest compression occurred when the defendants were alone with Tyler in their home.
"Subsequent investigations discovered that Tyler had sustained serious injuries before his death, including fractured ribs, that could only have been caused while he was in the care of his parents."
Claiming one neighbour had heard a high-pitched scream, while another described hearing a loud bang, Mr Smith said: "The prosecution say that Luke Morgan and Emma Cole were plainly arguing in the early hours.
"Their argument took place at a time when they had both been drinking alcohol."
After paramedics arrived at the couple's home, the court heard Morgan said he believed Tyler's collapse was a "cot death" and claimed he had been unable to wake him.
Tyler, who was in cardiac arrest, was taken to Walsall Manor Hospital, arriving at 3.40am, and was pronounced dead at 4.03am.
Following the verdicts, Judge Michael Chambers Chambers QC said the offences clearly crossed the custody threshold.
Before bailing the defendants until June 21, the judge thanked the jury and told the panel members: "That ends your role in this case - a case which has lasted since the beginning of April.
"I will need to adjourn the case to decide the appropriate sentence. Almost certainly I will need the assistance of the Probation Service in preparing the appropriate reports.
"I will have to very carefully consider balancing the aggravating and mitigating circumstances."
Speaking after the verdicts were announced, Detective Chief Inspector Victoria Downing of Staffordshire Police said: "Our first thoughts are with Tyler, who was barely two months old when he lost his life, and his extended family.
"This has been a difficult and distressing case to bring before the courts and we are grateful to those who have provided evidence to allow the jury to reach this decision."