The Duggar family from 19 Kids and Counting just celebrated their son-in-law Derick Dillard's 26th birthday, weeks before the newest addition to his family, Baby Dilly, arrives.

The family shared a photo of Derick, his wife Jill Duggar and her parents Jim Bob and Michelle as well as Derick's mother Cathy Byrum on their Facebook page and wrote, "We had a great time tonight celebrating Derick's 26th birthday a couple of days early. It is really amazing when your baby girl is getting ready to have her own 'birth' day!"

Jill will be the first Duggar daughter to give birth, and she will be having Baby Dilly's "birth" day on March 26, 2015.

Derick also shared a group photo on his Instagram account (@derickdillard) of grandmothers Michelle and Cathy holding Jill's tummy. "Hanging out with the grandmas!" Derick captioned the photo.

Meanwhile, Jill revealed what her husband got as presents for his birthday on her Instagram account (@jillmdillard), which in the end were gifts for Baby Dilly! In a photo post, a smiling Derick is seen holding up a baby book and a onesie.  Jill wrote, "We love these baby gifts @derickdillard got for his birthday! :-) So fun!"

The adorable onesie even had instructions for clueless fathers on how to get the baby in and out of the clothing. "You can do this Dad," is written in the onesie with arrows pointing to where the baby's head, arms, and legs should go.

It seems like Derick also received a brand new moustache mug that has "His" written on it. He shared a photo of Jill drinking from his new mug and he wrote, "Yep, she's mine!" And he hashtagged the photo with #loveher.

At 37 weeks, Baby Dilly is already "about the size of a large cantaloupe," the family revealed on Facebook, and he is "still packing on about a half an ounce per day or half a pound a week."