(CBS) Moms give birth to sons or daughters - pretty straightforward stuff. But when one English toddler grows up and starts a family, her child will be her own half-sibling.
At least that's the plan.
The toddler, two-year-old Mackenzie Stephens, was born without ovaries, so her 25-year-old mother, Penny Jarvis, intends to freeze her own eggs so that Mackenzie can use them someday to start her own family, the Daily Mail reported.
Jarvis, of Sheffield, England, told the paper she was devastated when she learned that Mackenzie would be infertile - the result of Turner Syndrome, a female-only genetic disorder that affects about one in 2,000 girls.
"She has three sisters and I couldn't imagine her growing up and watching them all have children while she couldn't have any of her own," Jarvis said. "Obviously, every mother wants to be a grandmother someday - that's what they dream of."
Jarvis said she read up on Mackenzie's condition and discovered that egg donation was a possibility.
But not everyone thinks the plan is such a great idea. Some medical ethicists say it could cause psychological problems for the mother - in this case Mackenzie - and leave her child confused about the relationship with her mother and grandmother.
"One can fully understand the sadness for a mother to discover that her little daughter suffers from Turner Syndrome, but I do not think putting her own eggs in the freezer is either a practical or an ethical solution," Josephine Quintavalle of Comment on Reproductive Ethics, told the paper. "Psychologists are already talking about the trauma of genealogical bewilderment, as egg and sperm donation and surrogacy create more and more artificial conceptions."
As for Jarvis, she seems unconcerned.
"A few people have told me they think it's a bit sick, but on the whole people have been supportive," she told the paper. "You could look at it as Mackenzie giving birth to her own brother or sister, but I choose not to see it like that."
Whatever you say, Mom. Or is it Grandma?