Credit: ABC News

Kelly Bates doesn't look like she gave birth to her 19th baby five short weeks ago.  Then again she always says she's been pregnant more often than not during her adulthood.   She's never had a C-section or twins.  She gave birth to 14 of her kids at home without so much as an aspirin.

The newest baby, Jeb Colton, was born in a hospital weighing 7 pounds, 8 ounces.  He has the same chubby cheeks and light blue eyes that many of his 18 older brothers and sisters did as babies.

As you might have guessed, the Bates are evangelical Christians who decided in their words, "to let the Lord decide how many children we would have."

Gil says, "if the Lord were to give us more children, me and my wife would both be excited.  It would be like saying more blessings."

They made a faith-based decision not to use birth control early in their marriage.  And yet, at 45, Kelly is reaching the outer reaches of her fertility.  She began using hormones to strengthen her uterine wall after she miscarried more than once.  They feel strongly that while they would never take fertility medicine, once there is conception, they feel morally obligated to treat an embryo medically as if it were one of their full-grown children.  "If my son fell overboard on a boat, we would do everything we could to save him" Gil says. And that's how they feel about helping a pregnancy remain viable.  For the Bates life very much begins at conception.

Watch the full story on " Nightline" TOMORROW  at 11:35 p.m. ET

The 19 Bates children whose ages range from 23 to 6 weeks old -  all live with their parents under one rambling roof in their five bedroom home in Lake City, Tenn. The family lives modestly, buying most things - like bikes and shoes and clothes - second hand.  Dad and the older brothers run a tree-cutting business.  But they have to stretch to make their weekly grocery bills which includes seven gallons of milk and nine loaves of bread.

Credit: ABC News

They say they're not trying to catch up to the Duggars, the TLC stars of "19 Kids and Counting".  The two families have been close friends since their adult children were very young.

Both families now have 19 kids and counting.  And since appearing in ABC's "Primetime Nightline: (Extra)Ordinary Family" hour last summer, the Bates have signed on for their own TLC reality show called "The Bates Family: Baby Makes 19," debuting Tuesday at 10 p.m. ET/PT.

But I asked the Bates if they are worried that celebrity might spoil their kids?  And I don't mean spoil like indulge, but spoil like milk.  And they said no.  They are convinced that their family will be able to hold onto their conservative values and lifestyle even with camera crews following them around.

Their kids are home schooled by Kelly with a big dose of Bible study.  They dress modestly (long shirts, no pants for the girls.  No shorts for the boys).  They aren't allowed to watch regular TV.  Their idea of a good show is a 1950's character study like "Roy Rogers".

I asked Lawson, the square-jawed, clean cut second son if he'd ever heard of Snooki - the crass, hard-partying star of "Jersey Shore"?   and  he looked at me and said sincerely, "is that a dog'?"

"How about Kim Kardashian, ever heard of her?"  I asked.  "Uh,"  you could see him racking his brain and then replied trying to be nice, "uh, No."

Lawson, 19, and has been the family grocer for years.  How many teenage boys do you know how can tell you the price of a pound of cold cuts and whether it's gone up in the past few weeks.  He also runs his own successful lawn care business, when he's not taking college courses.

The oldest son Zach was elected the youngest county commissioner in Tennessee.   The entire family campaigns on behalf of Rick Santorum.

"We like his consistency", says Zach who praised his values and his staunchly pro-life stance.

All their kids play either guitar or piano or fiddle or all three.  They often sing at elder care facilities or at church. Several of their kids are volunteer EMT's.  Some of the older girls are on a mission helping street children in Peru.

They contribute to their community, but they also all chip in at home.  The kids help around the house in a way that makes visitors marvel.  Michaela, the oldest daughter organizes the nearly four hours of laundry that's needed every day. Erin is a concert pianist with 2 DVD's, but she also teaches her younger siblings.

The house is run like a mess hall for kids… with a long cafeteria style picnic table and lots of pitching in.   Alyssa has been cooking meals for 20 people since she was 12 years old.

"I don't want them to see it as a chore" says mom Kelly who somehow manages to keep the house running while tending to yet another newborn.