The three babies lie in plots next to each other, their names etched in a single stone: Jamie, Corey, Abby.
Each was found in the Mississippi River southeast of the Twin Cities, four years apart, discarded soon after birth.
No one knows who their mothers are, but it's easy to know who is caring for them.
"To have a child by themselves, it's a hard one. I just don't want them to be alone, I guess, is probably the whole thing," said Jeanne Madtson, who along with her husband, Don, donated the space to bury the infants.
There was a funeral in 1999 when the little girl was found, wrapped in a towel.
Another was held in early 2004 after the baby boy turned up.
When the third baby surfaced, a girl in 2007, the Madtsons gave them all a common tombstone.
Now that a fourth newborn has been found in the river - a 7-pound girl sealed in a plastic bag discovered Monday just south of Winona - Madtson said she wants to care for her, too.
"I don't want them to just bury her and not have anybody around her," Madtson said. Whether that means making more room at her family burial plot in Red Wing's Oakwood Cemetery or finding a space somewhere in Winona, so be it, she said.
Madtson has not talked to the sheriff's office in Winona County, where the baby girl was found, but has asked investigators in Goodhue County, where the other three babies turned up, to pass along her name and phone number when the time comes for burial.
Investigators have no leads in any of the cases and are asking for the public's help in figuring out how the children ended up in the river.
For the Madtsons, each new discovery brings up their own daughter - stillborn in 1989 - who is buried alongside the babies found in the Mississippi.
Jeanne Madtson remembers the anguish of seeing her child for the last time at the funeral home.
"I held her for over an hour, and then it was time. I laid her in a casket, and then they closed it. And that was it," she said. "I can't believe the mothers of these four children will be able to live with themselves. I can't imagine living with the fact that I threw a baby in the water and then go on with life."
Burying the children - naming them, even - is Madtson's way of showing the children that they are loved.
"I think everyone deserves a proper burial," she said.