A Michigan man whose 13th son was just born says he's convinced that "medically, it's just not possible" for him and his wife to produce a daughter.

He also says it's proving a challenge to agree on a name for their newborn.

Forty-year-old Jay Schwandt tells The Grand Rapids Press (http://bit.ly/1IDEnMC ) the boy born Wednesday is the second he and his wife, Kateri, have had who arrived with a full head of hair.

The baby and his 40-year-old mother are doing well at Mercy Health Saint Mary's Hospital in Grand Rapids. The boy is 22 inches and weighs 8 pounds, 9 ounces.

The couple live in the Grand Rapids suburb of Rockford. They say they stuck to their tradition of not knowing the baby's sex ahead of time.