Nicholas Kuras is only 14-months-old and in critical condition. Police believe his father's girlfriend responsible but it is not clear how long it has been going on.
The baby's mother died from a sudden asthma attack when he was just 5 months. Rachel Grosso, who was like a second mother, moved into their Eastpointe home to help Kevin Kuras care for his infant.
But it took a turn last February when Rachel and her husband moved out and Kevin Kuras began spending more time with his girlfriend, 37-year-old Hilary Ulp.
She says the warning signs were there.
"He said every time Hilary walked in the baby would cry," Grosso said. "I kept telling him that's a red flag. Babies love everybody."
And then last Friday her fear became a reality.
FOX 2 is told Thursday night that Kevin went to play cards and left Nico with his girlfriend. By Friday morning, the baby was unresponsive.
"I went in there to pick him up and he was stiff," said Kevin Kuras in a phone interview. "His head went all the way back and that's when I said call 911 and held him."
Nico rushed to the hospital with a broken pelvis, collar bone, four broken ribs and had bleeding in the brain.
Investigators eventually determined Hilary was responsible. She has since been arrested and charged with first degree child abuse.
Kevin now sits at his baby boy's bedside inside St. John Providence Hospital hoping and praying Nico will recover.
"The doctor said she picked up, squeezed his frame and shook him," Kevin said. "I don't know what happened. She was jealous and insecure of everything. But I didn't know she was jealous of my son. You are a monster to do this to a kid bottom line."
"I'm praying to God there is no long-term damage," Grosso said. "If he does live, that he is safe and can grow up. That he doesn't suffer."
At first Hilary and kevin were arrested but Kevin was released by police. Investigators consider the case a situation of shaken baby syndrome.
Ulp, who is divorced, has an 11-year-old child. There has been no reports of any abuse as of yet, but the investigation is ongoing.