The Duggar family has celebrated their first birthday of the year.

Twins Jana Marie and John-David Duggar, born on January 12, 1990, turned 25 yesterday. The two, who came into the world two years after the eldest Duggar child Joshua James, are the oldest set of twins in the 19 Kids and Counting household.

To celebrate the occasion, parents Jim Bob and Michelle, along with Grandma Duggar, took the pair to Cracker Barrel.

A picture posted on the official Duggar Family Facebook page shows the five Duggars having dinner at what they say is one of their favorite restaurants. Another photo shows the twins posing side by side.

Jim Bob and Michelle wrote as a caption to the photos: "[Jana and John] both have a ministry heart and are great role models for other young people ... We are so blessed to have such wonderful daughters and sons! Happy 25th Jana and John!"

A recent post in the Duggar Family blog shares that Jana, aside from being involved in various ministries, is also a concert pianist. John, on the other hand, has recently earned his pilots license and is busy doing construction work and serving as a Washington County constable.

Last Friday, the twins' parents posted a throwback picture that shows an infant Jana and John.

The photo is captioned "Children are a blessing from God! A #tbt to nearly 25 years ago. I'm sure many of you know who these two beautiful babies are. Even though they grow up fast, we are so blessed to see how God works in the lives of our children."

Jana and John, who are the oldest Duggar offsprings still living at home, are both single. Though rumours saying the two have started dating have emerged, no official news has come out.

In November, John jokingly told TLC producers when asked if he is seeing anybody, "No ladies in my life yet, at least not so as anyone can know."

He confirmed in a more serious tone, "No ... there's absolutely no ladies in my life right now."

Jana, on the other hand, was previously rumoured to be dating Christian football player Tim Tebow, but a representative of the athlete said that the two have not even met.