On Tuesday's "19 Kids and Counting" episode, "Anna's Having a...," the Duggar family threw Josh and Anna Duggar a gender reveal party. It was revealed the couple's fourth child will be a girl.

Anna hired an ultrasound technician to visit the family's Washington, D.C. home so her three older children could have a sneak peek of their youngest sibling in an ultrasound. The technician wrote the baby's gender on a piece of paper and sealed it in an envelope so the couple could open during their Arkansas baby shower.

"I want mommy to have a little girl because we have two boys and so I need another little sister," the oldest Duggar grandchild, Mackynzie, said.

Her father Josh hoped for another Mini-Me.

"I really think it's going to be a boy," he said.

Josh and Anna planned a trip to California alone before the birth of their fourth child. Their first stop was in Arkansas to drop off their three children with grandparents Jim Bob and Michelle Duggar. They also visited newlyweds Ben and Jessa Seewald in the house they once occupied when first married.

Their two children, Mackynzie and Michael, were born in that home.

"I think it's a place that has a lot of sentimental value to us," Josh said, as he and Anna looked over the renovations Ben and Jessa made.

Once in California, Josh and Anna went to Santa Monica where they enjoyed amusement park rides and carnival games on the pier.

Sierra, the party planner who organized the Seewald's wedding, called a family meeting to get ready for Josh and Anna's big event.

When Josh and Anna arrived back in Arkansas and drove to the Duggar family home, they found homemade signs on the roadside and a flock of pink and blue flamingos stuck in the front yard. Once inside, the family surprised the parents-to-be by shooting confetti into the air. Pink confetti. The baby will be a girl!

"19 Kids and Counting" airs Tuesdays at 9 p.m. ET on TLC.